* docs: goleveldb is much more stable now
Refs https://github.com/syndtr/goleveldb/issues/226#issuecomment-682495490
* rpc/core/events: make sure WS client receives every event
previously, if the write buffer was full, the response would've been
lost without any trace (log msg, etc.)
* rpc/jsonrpc/server: set defaultWSWriteChanCapacity to 1
Refs #3905Closes#3829
setting write buffer capacity to 1 makes transactions count per block
more stable and also reduces the pauses length by 20s.
before: https://github.com/tendermint/tendermint/issues/3905#issuecomment-681854328 net.Read - 20s
after: net.Read - 0.66s
* rpc/jsonrpc/server: buffer writes and avoid io.ReadAll during read
Migrates the `rpc` package to use new JSON encoder in #4955. Branched off of that PR.
Tests pass, but I haven't done any manual testing beyond that. This should be handled as part of broader 0.34 testing.