opt: avoid redundant calls to ResetBuffer()

fix: supplement all the formal protocol formats of TCP and UDP

opt: improve the implementation of Least-Connections load-balancing

Leverage min-heap to optimize Least-Connections load-balancing

mod: upgrade dependent modules

trifle: use more formal flags for eventfd

opt: improve the creation processes of netpoller

Fixes panjf2000#72

trifle: use customized logger to log errors instead of std log package

ci: exclude golangci-lint from Windows

trifle: enable ReadN(int) to handle corner cases

opt: lazily allocate memory for ring-buffers