chore: sort imports in internal/socket

fix: resolve the contention issue in internal logger

fix: resolve the contention issue in internal logger

trifle: remove redundant test code

fix: prevent servers from panicking reads in closed sockets

Fixed panjf2000#194

opt: improve the logic of preventing server blocking

trifle: refine ReadBufferCap option and add comments

doc: update the description about ring-buffer

trifle: add comments for exported functions

opt: keep running when an error occurs in connection

Fixes panjf2000#142