DEV: Created func to scrape default param values during autowrap

Function is called _default_vals.
This fuction will be used by the function define_input_ports when
functions are being autowrapped into VisTrails objects.
BUG: Commented modules.yaml entries that caused probs

These commented functions are temporary removals that should be fully
functional after default value assignment is merged into master
Merge remote-tracking branch 'refs/remotes/giltis/default_scrape' into wrap_extension

Conflicts:
	vttools/wrap_lib.py