tests: add glob matching for unified tests
This adds a " (glob)" marker that works like a simpler version of
(re): "*" is converted to ".*", and "?" is converted to ".".
Both special characters can be escaped using "\", and the backslash
itself can be escaped as well.
Other glob-style syntax, like "**", "[chars]", or "[!chars]", isn't
supported.
http://mercurial.selenic.com/bts/issue436
$ hg init
$ hg -v log -v
$ hg -v log -v x