Make pip quieter when installing packages on Travis-CI.
Bring "Testing Policy.txt" into line with the changes I've made so far.
Fix output folder name generation as revealed by tartest.tar

(I definitely still have a long way to go in decomposing tryExtract)
Remove unmakeself and unshar from the extractor definitions.

- unshar doesn't unpack safely and I doubt unmakeself does either
- unshar doesn't fail cleanly, which breaks the functional tests
Treat UnsupportedFiletypeError as "skip test"... at least for now.
Move legacy, unmigrated, or potentially non-functional stuff to "unsorted"