Various improvements to test script command line options, i.e. --type
The following changes were made:
* Create --type parameter which accepts 'htmlpurifier', 'phpt', 'vtest', etc.
in order to execute only that class of tests. This supercedes --only-phpt.
* Create --quick parameter for multitest.php, run only the tips of each
release series.
* Create --distro parameter for multitest.php, supercedes --exclude-normal
and --exclude-standalone.
Also, a grep for htmlt tests was added, although add_tests() doesn't do
anything with it yet.
Signed-off-by: Edward Z. Yang <edwardzyang@thewritingpot.com>