back to string instead of IFeature
adding feature type and true/false specifications
removing InMemoryConfiguration and ToggleCheckerFactory. No need to have them in test.
adding test for multiple specifications
rename parameter configFlag to flag name according to new xml documentation
moving and renaming test file
ToggleChecker shouldn't allow duplicate feature flag configurations
adding r# file for solution
removing some using directives
restructuring the tests in different fixtures