v0.6.0

Feat

[#610] feat(http1): support flush chunk in handler
[#474] feat: support HTTP trailer

Fix

[#625] fix: connection pool leak
[#633] fix: panic when add 'trailer' to header
[#622] fix: switch 'Trailer' to pointer to avoid cycle dependencies
[#585] fix: skip rest chunked body correctly
[#401] fix: ClientIP handling is unsafe

Chore

[#627] build: update sonic & golang version in ci
[#600] chore: use 'ioutil' to avoid compilation failures

Docs

[#595] docs(README): add cache, etag, casbin extensions description
Thanks a lot to those community contributors who submit some pull requests for this version:
@byene0923 @BaiZe1998 @L2ncE