v4.1.3

[minor] added webgo.ResponseStatus(rw http.ResponseWriter) int which returns response status code
[patch] fixed a bug which did not send appropriate JSON response header for the convenience methods
[patch] fixed accesslog middleware not printing valid http status code when not using webgo response methods
[patch] fixed regression introduced in 4.0.4, where default http status was 0, now it's set to 200
[patch] refactored accesslog & CORS middleware (moved to new package)
[patch] refactored global logger for improved modularity
[patch] Removed unnecessary WriteHeader from SendResponse, SendError. Added relevant header write for Send
[-] added handler which directly writes using w.Write where 'w' is the http.ResponseWriter, in cmd/main.go
[-] added tests for logger
[-] no performance impact with these changes
[-] removed the empty deprecation logs function
[-] removed unwanted comments from cmd/main.go
[-] updated README with correct version number & updated important section highlight the regression
[-] updated README with correct version number and updated the sample code
[-] updated tests to test if w.Write([]byte) where 'w' is the http.ResponseWriter, works as expected