Use buffered channels for websocket listener.

[arijitAD]

Issue summary

• Since, an unbuffered channel is blocking, it is 4x slower than a buffered channel.
• Channels should always be buffered unless we need blocking behaviour.

BenchmarkBufferedChannelEmptyStruct-8         23657084            49.9 ns/op
BenchmarkBufferedChannelOneByte-8             21230530            54.6 ns/op      18.31 MB/s

BenchmarkUnbufferedChannelEmptyStruct-8        6075384            177 ns/op
BenchmarkUnbufferedChannelOneByte-8            6341457            184 ns/op       5.44 MB/s

Other information and links

• https://tpaschalis.github.io/channels-limitations-speed/

[edwardmack]

Closed, this issue was addressed in PR #1668.