Added an overloaded MapHubs to allow using middleware

- Added a unit test for the overloaded MapHubs method
- Added a sample that uses headers to authorize using owin middleware

#1800
Made changes as per code review feedback

#1800
Added extra tracing to the DisconnectFacts

- This also involved adding extra tracing functionality to the
HostedTest class
Added overloaded MapConnection method to allow adding owin middleware

- Added tests for MapConnection methods
- Made changes as per code review feedabck for MapHub overload
#1800
Merge branch 'release' into dev