Added DriverSettings.cs; moved DefaultTestAssemblyBuilder and DefautTestAssemblyRunner to Api namespace
Modify the framework so that it only returns an error element when an unexpected exception occurs. Add functional tests for FrameworkController
Make sure OneTimeSetUp errors actually show up on the nunit-console report
Add tests of CountTestsAction
Remove code to return formatted errors and allow unexpected exceptions to pass through. Exceptions in user code must still be trapped elsewhere in the framework, so if any show up at this level, seek the bug elsewhere.
Replace some inline constants with values from DriverSettings
Merge pull request #124 from nunit/framework-api

Merging this and the corresponding nunit-console PR.
Keeping the branch for further work.