Add python_test(), update deps as needed to fix tests, was missing webcolors and ipafonts
dependencies (not listed in setup.py.
Fix test failure in python-2.7 due to test needing to be updated to same as py3
NOTE: requires FEATURES=-network-sandbox for test_command.py (to fetch some icons)
Package-Manager: Portage-2.3.5, Repoman-2.3.2_p30
The tests give the same number of failures with all Python versions.
There are some additional deprecation warning for python3.6 but they do
not cause errors yet.
