#120, solving cyclic packaging dependencies, Moved Context (as inner class) to ConversionContext in model.common, corrected BuildIn to BuiltIn, all requested built-in methods added
#120 Method and BuiltInMethod implement a common interface that can be used for matching.
#120 Moving BuildInMethod to the source model
#120 Renaming Method to SourceMethod
#120 Renaming BasicMethod to Method