transformations can have priorities now.
they will be ordered by their priority so that some query operations can be done before the actual changes happen.
right now i missuse the working transformations for quering tasks but in future revisions this will change.
i just want to get the job done.

rename variable is now working based on mangled names.
so that the mangled names are used to identify the different occurences of variables in multiple files.
this way one can also detect occurences of variables that are declared extern and dont use the same header as others.