Change HTTP Handlers->Tasks
Rename HTTP Controllers->Handlers
Fix wrongly named controllers
Get Handler->Task and Controller->Handler renaming working
Correct Indenting
New cpp-common ref
Take latest cpp-common
Merge remote-tracking branch 'origin/dev' into Rename_Handler_Branch

Conflicts:
	src/ut/mockdiameterstack.hpp
	src/ut/mockhttpstack.hpp
Merge pull request #135 from Metaswitch/Rename_Handler_Branch

[Reviewer: Alex - Do not merge] Rename handler branch