Add --all, **kwargs to typ.main().

Two features added for switching Chromium over ...

There's a new '--all' flag that will override --skip and
@unittest.skip and @unittest.skipIf.

Also, the typ.main() entry point and the runner.parse_args()
call now take an optional **kwargs dict of values that can be
used to set the defaults used to parse arguments. This makes it
easier for wrapper scripts to set defaults for directories to use,
tests to skip, etc.

This works even for the 'tests' arg for the remaining command
line arguments.

Lastly, I fixed some inconsistencies that can arise in Python 2.7's
unittests' handling of realpath() vs. abspath() (see
http://bugs.python.org/issue19352).
lint
bump version to 0.8.4