Merge pull request #441 from pastoso/master

Handle status == ok on codeRequest response.
Fixed version mismatch in WHATSAPP_VER and WHATSAPP_USER_AGENT
Replaced MD5 identity with SHA1

Fixes #443
Merge branch 'master' of https://github.com/venomous0x/WhatsAPI
Fixed sending and responding to receipts
Cleaned up duplicate code

As done by davidgfnet
https://github.com/davidgfnet/whatsapp-purple/commit/6205fcffd988f0986410fd74f77b814f2ae3c368
fire onGetStatus event when receiving a message from @s.us