v0.5.0

Optimize

1. [#274] optimize: increase first bookSize to 8KB to reudce overhead for connection read at begin
2. [#273] optimize: ignore EOF when read a closed connection

Fix

1. [#283] fix: protect operator dont be detach twice
2. [#280] fix: detach operator race
3. [#278] fix: OnRequest should wait all readable data consumed when sender close connection
4. [#276] fix: compile error
5. [#238] fix: close conn when server OnRequest panic

Docs

1. [#243] docs: rm outdated info