Add skeleton for dmark USSD transport.
Document how the Dmark protocol is expected to work.
Add package __init__.py for Dmark transport.
Flesh out Dmark USSD transport.
Fix up some missing inlineCallbacks and harden logging against non-ascii characters.
Add optional authentication to HTTP RPC base class.
Add tests for authentication helpers.
Remove unused username and password configuration parameters from tests.
Add tests for authorization.
Add transport_type to DmarkUssdTransport.
Tests for DmarkUssdTransport (heavily inspired by ImiMobile tests).
Fix references to ImiMobile.
Merge branch 'feature/issue-703-dmark-ussd-http-transport' into develop