Implement a fd logging hook
Allow diameter to specify a trail ID on sent messages
Log the diameter message
Code tidy up
Fix mock diameter stack
Improve error handling
Fixes and markups
Fix compiler error
Pass the event ID and trail ID to SAS::Event in the right order
For incoming requests store new trail ID in PMD
Merge remote-tracking branch 'origin/master' into diameter-sas-ladder

Conflicts:
	src/diameterstack.cpp
Update resource bundle ID
Merge pull request #197 from Metaswitch/diameter-sas-ladder

[Reviewer: Matt] SAS logging from freeDiameter