API changes
Boilerplate for new APIs
Make AppServerTsx constructor public.  Needed to allow API implementation to create default object if app server decides not to handle a transaction
Fix up mock appserver for new APIs
Add optional reason parameter to cancel_fork API
Merge master in to svc_api branch
Fix failing UT
Practical updates to the timer API
Merge pull request #7 from Metaswitch/timer-api-updates

Reviewer Mike - Practical updates to the timer API
Add original_request() API to AppServer interface
Add new API
Add route_hdr() API
Add mock for route_hdr API
Merge pull request #8 from Metaswitch/svc_api

Svc api