Title: Macro support for Generalize, part I. (variable replacement)
Goal: accept
Parameters: [{file,"gen_mac1.erl"},{posrange,{95,95}},{varname,"T"}].
Documentation: Generalize "2" in myfun/1 using a variable replacement, where myfun is used inside a macro body. The transformation should insert the expression 2 into the argument list of the application inside the macro definition, and modify the syntax tree accordingly.
