* fix runtime.GOOS=="windows, add some test cases
test cases are still limited for flag
* update to latest fiber v2.4.0 & libwebp v1.2.0
manually test confirmed
* upgrade to fiber v2
* code format
* remove redundant variables
* remove useless exportable variables/functions
* go mod replace
use our own mirror now.
* add test case for converter, use deferInit to make test more simple
* remove useless file and fix typo
* Makefile change
* upgrade to go 1.15
* remove wrong go test comments
* complete test case, coverage, coverage badge
* Fix version typo
* config struct fix
* add banner, show version, add server header, remove fiber startup message
Co-authored-by: n0vad3v <n0vad3v@riseup.net>