Added support for close session with test
Test for resume, with reply resume
Test for begin with end session
pep8 fixes
Some tests covering failure cases
Moved error handling
Tests: empty 'in_reply_to' field and failed vumi request
eof new line added
Rearranged outbound to return early on error
Improved error messages
Refactored errors in inbound message
Check message[''] instead of message.payload
Merge pull request #2 from praekelt/feature/handle-close-event

Feature/handle close event