Deletes CSharpIRToken to use the more general RazorIRToken class.
Rather than using the visitor to visit tokens, now writing a
CSharpExpresionIRNode is an 'atom', and will write its tokens itself.
- Added DirectiveRemovalIRPass
- Added IRazorDocumentClassifierPhase, IRazorDirectiveClassifierPhase and
IRazorIROptimizationPhase
- Added all the related passes and default implementations
- Refactored DefaultDirectiveIRPass to do the right thing
- Execute method in IR passes now return void
- Added tests for the new phases
Ryan Nowak
Ajay Bhargav Baaskaran