Have only one jamoma_callback_return_type value message

[nwolek]

Remove the typed version of jamoma_callback_return_type

Found here: https://github.com/jamoma/JamomaMax/blob/master/library/source/JamomaModularForMax.cpp

There is a lot of duplication of code between the typed and untyped versions of this method. There is little need for two, so they need to be merged into a single untyped version.

During code review 5 March Bergen.