Minor tweak to act()-based functions for clarity.
Library func work, no reorg in this commit.

* fix pwheren()
* add a handful of library functions
* add lib/skunk.m for experimental stuff
Add library license info.
Merge branch 'master' of https://github.com/adobe-research/mesh
update .gitignore to ignore all *.iws (IJ workspace state)
more .gitignore sprucing
update test_library.m to track changes:
* pwheren fix
* trace renamed to tconverge
Merge remote-tracking branch 'upstream/master'

Conflicts:
	src/script/lib/misc.m
	src/script/lib/mutate.m