Rename IValidatorAdapter back to IModelValidator, as the latter is more description of its end use
Add test code coverage for ValidatingModelBase
Couple lines more coverage
Add support for running coverage for integration tests
Add tests for CommandAction and EventAction
Push code coverage up to 98.7%, including integration tests
More test stuff
Use Dispatcher instead of SynchronizationContext for synchronization.

It looks like the SynchronizationContext can now change on the same thread
(see http://msdn.microsoft.com/en-us/library/system.windows.basecompatibilitypreferences.reusedispatchersynchronizationcontextinstance%28v=vs.110%29.aspx)
meaning that we can no longer do a reference comparison between SynchronizationContext.Current
and the captured SynchronizationConext to check whether a dispatch is required.
It turns out we shouldn't have been doing this anyway.... So switch to using a Dispatcher,
which does support this stuff.

Additionally, Execute now uses an IDispatcher, which means the implementation can be switched
again in the future. It also makes unit testing easier....
Fix Rakefile for people who haven't restored nuget packages yet
Push coverage up to 99.7%