code use proper functions to get paths.
Changed the name of tar file that is searched for to be absolute (i.e., not use
os.extsep) since filename is locked in based on name of file in CVS
(testtar.tar).
Closes bug #731403 .
and test_support.run_classtests() into run_unittest()
and use it wherever possible.
Also don't use "from test.test_support import ...", but
"from test import test_support" in a few spots.
From SF patch #662807.
- the test was sloppy about filenames: "0-REGTYPE-TEXT" was used where
the archive held "/0-REGTYPE-TEXT".
- tarfile extracts all files in binary mode, but the test expected to be able to
read and compare text files in text mode. Use universal text mode.