added SimpleEnum to AssemblyToProcess
added a testclass DebuggerDisplayInjectorTests with the first test EnumShouldNotGetDebuggerDisplay
changed DebuggerDisplayInjector.AddDebuggerDisplayAttributes to skip Enums
fixed the default value (None) of SimpleEnum
Merge branch 'RobertGiesecke-feature/no-debuggerdisplay-for-enums'
Fixed up tests. Bumped version.