* tools/tm-bench: Don't count the first block if its empty
* Try melekes suggestion
* Fix getting the start time so the first block is no longer empty
* Fix changelog entry
* Make code smell better
* tools/tmbench: Fix the end time being used for statistics calculation
Previously we were using the time at which all connections closed in statistics, not
the time after {duration} seconds.
* Use waitgroups for starting up
At larger tx sizes (e.g. > 10000) we were spending non-neglible
amounts of time in tx creation, due to making the final bytes random.
The slower the send loop, the less accurate it is at measuring the time
tendermint took. (As we can't reach the promised contract of the given rate)
There really isn't much need for that randomness, so this PR makes it
such that only the txNumber gets bumped between txs from the same
connection, thereby improving sendloop speed and accuracy.