Initial Trust Metric Implementation

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p2p: netPipe for <Go1.10 in own file with own build tag

Follow up of 283544c7f3
putting <Go1.10 implementation of netPipe in its own
file and protect it with its separate build tag.

p2p: use fake net.Pipe since only >=Go1.10 implements SetDeadline

Fixes https://github.com/tendermint/tendermint/issues/851

Go1.9 and below's net.Pipe did not implement the SetDeadline
method so after commit
e2dd8ca946
this problem was exposed since now we check for errors.

To counter this problem, implement a simple composition for
net.Conn that always returns nil on SetDeadline instead of
tripping out.

Added build tags so that anyone using go1.10 when it is released
will be able to automatically use net.Pipe's net.Conns

p2p: peer should respect errors from SetDeadline

rpc: wait for rpc servers to be available in tests

fix TestFullRound1 race (Refs #846)

Noticed while auditing the code that we aren't respecting
(*net.Conn) SetDeadline errors which return after
a connection has been killed and is simultaneously
being used.

For example given program, without SetDeadline error checks
```go
package main

import (
  "log"
  "net"
  "time"
)

func main() {
  conn, err := net.Dial("tcp", "tendermint.com:443")
  if err != nil {
    log.Fatal(err)
  }
  go func() {
    <-time.After(400 * time.Millisecond)
    conn.Close()
  }()
  for i := 0; i < 5; i++ {
    if err := conn.SetDeadline(time.Now().Add(time.Duration(10 * time.Second))); err != nil {
      log.Fatalf("set deadline #%d, err: %v", i, err)
    }
    log.Printf("Successfully set deadline #%d", i)
    <-time.After(150 * time.Millisecond)
  }
}
```

erraneously gives
```shell
2017/11/14 17:46:28 Successfully set deadline #0
2017/11/14 17:46:29 Successfully set deadline #1
2017/11/14 17:46:29 Successfully set deadline #2
2017/11/14 17:46:29 Successfully set deadline #3
2017/11/14 17:46:29 Successfully set deadline #4
```

However, if we properly fix it to respect that error with
```diff
--- wild.go 2017-11-14 17:44:38.000000000 -0700
+++ main.go 2017-11-14 17:45:40.000000000 -0700
@@ -16,7 +16,9 @@
    conn.Close()
  }()
  for i := 0; i < 5; i++ {
-   conn.SetDeadline(time.Now().Add(time.Duration(10 * time.Second)))
+   if err := conn.SetDeadline(time.Now().Add(time.Duration(10 *
time.Second))); err != nil {
+     log.Fatalf("set deadline #%d, err: %v", i, err)
+   }
    log.Printf("Successfully set deadline #%d", i)
    <-time.After(150 * time.Millisecond)
  }
```

properly catches any problems and gives
```shell
$ go run main.go
2017/11/14 17:43:44 Successfully set deadline #0
2017/11/14 17:43:45 Successfully set deadline #1
2017/11/14 17:43:45 Successfully set deadline #2
2017/11/14 17:43:45 set deadline #3, err: set tcp 10.182.253.51:57395:
use of closed network connection
exit status 1
```

```
==================
WARNING: DATA RACE
Write at 0x00c42d7605f0 by goroutine 844:
  github.com/tendermint/tendermint/consensus.(*ConsensusState).updateToState()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state.go:465 +0x59e
I[11-14|22:37:28.781] Added to prevote                             vote="Vote{0:646753DCE124 1/02/1(Prevote) E9B19636DCDB {/CAD5FA805E8C.../}}" prevotes="VoteSet{H:1 R:2 T:1 +2/3:<nil> BA{2:X_} map[]}"
  github.com/tendermint/tendermint/consensus.(*ConsensusState).finalizeCommit()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state.go:1229 +0x16a9
  github.com/tendermint/tendermint/consensus.(*ConsensusState).tryFinalizeCommit()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state.go:1135 +0x721
  github.com/tendermint/tendermint/consensus.(*ConsensusState).enterCommit.func1()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state.go:1087 +0x153
  github.com/tendermint/tendermint/consensus.(*ConsensusState).enterCommit()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state.go:1114 +0xa34
  github.com/tendermint/tendermint/consensus.(*ConsensusState).addVote()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state.go:1423 +0xdd6
  github.com/tendermint/tendermint/consensus.(*ConsensusState).tryAddVote()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state.go:1317 +0x77
  github.com/tendermint/tendermint/consensus.(*ConsensusState).handleMsg()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state.go:565 +0x7a9
  github.com/tendermint/tendermint/consensus.(*ConsensusState).receiveRoutine()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state.go:523 +0x6d2

Previous read at 0x00c42d7605f0 by goroutine 654:
  github.com/tendermint/tendermint/consensus.validatePrevote()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/common_test.go:149 +0x57
  github.com/tendermint/tendermint/consensus.TestFullRound1()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state_test.go:256 +0x3c5
  testing.tRunner()
      /usr/local/go/src/testing/testing.go:746 +0x16c

Goroutine 844 (running) created at:
  github.com/tendermint/tendermint/consensus.(*ConsensusState).startRoutines()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state.go:258 +0x8c
  github.com/tendermint/tendermint/consensus.startTestRound()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/common_test.go:118 +0x63
  github.com/tendermint/tendermint/consensus.TestFullRound1()
      /home/vagrant/go/src/github.com/tendermint/tendermint/consensus/state_test.go:247 +0x1fb
  testing.tRunner()
      /usr/local/go/src/testing/testing.go:746 +0x16c

Goroutine 654 (running) created at:
  testing.(*T).Run()
      /usr/local/go/src/testing/testing.go:789 +0x568
  testing.runTests.func1()
      /usr/local/go/src/testing/testing.go:1004 +0xa7
  testing.tRunner()
      /usr/local/go/src/testing/testing.go:746 +0x16c
  testing.runTests()
      /usr/local/go/src/testing/testing.go:1002 +0x521
  testing.(*M).Run()
      /usr/local/go/src/testing/testing.go:921 +0x206
  main.main()
      github.com/tendermint/tendermint/consensus/_test/_testmain.go:106 +0x1d3
==================
```

Fix nondeterministic tests failures related to pubsub

p2p: comment on the wg.Add before go saveRoutine()

Fix/tests

Just noticed while auditing the code in p2p/addrbook.go,
wg.Add(1) but no subsequent defer.
@jaekwon and I had a discussion offline and we agreed to
comment about why the code was that way and why
we shouldn't move the wg.Add(1) into .saveRoutine() because
if go a.saveRoutine() isn't started before anyone invokes
a.Wait(), then we'd have raced a.saveRoutine().

Enable logs by default

docker update || 0.12.0

```
panic: interface conversion: interface {} is nil, not types.TMEventData

goroutine 7690 [running]:
github.com/tendermint/tendermint/consensus.waitForAndValidateBlock.func1(0xc427727620, 0x3)
        /go/src/github.com/tendermint/tendermint/consensus/reactor_test.go:292 +0x62b
created by github.com/tendermint/tendermint/consensus.timeoutWaitGroup
        /go/src/github.com/tendermint/tendermint/consensus/reactor_test.go:349 +0xa4
exit status 2
FAIL    github.com/tendermint/tendermint/consensus      38.614s

```

consensus: make mempool_test deterministic