* 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
## Description
This PR wraps the stdlib sync.(RW)Mutex & godeadlock.(RW)Mutex. This enables using go-deadlock via a build flag instead of using sed to replace sync with godeadlock in all files
Closes: #3242
## Description
this log message was marked as not useful and in the issue it was proposed to move it to debug. I am going with this path for now. After we have refactored the logger we shold go through the codebase in order to clean our log statements.
Closes: #2101
## Description
partially cleanup in preparation for errcheck
i ignored a bunch of defer errors in tests but with the update to go 1.14 we can use `t.Cleanup(func() { if err := <>; err != nil {..}}` to cover those errors, I will do this in pr number two of enabling errcheck.
ref #5059
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.
