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.
$ echo 'raise Exception("bit bucket overflow")' > badext.py
$ abspath=`pwd`/badext.py
$ echo '[extensions]' >> $HGRCPATH
$ echo "gpg =" >> $HGRCPATH
$ echo "hgext.gpg =" >> $HGRCPATH
$ echo "badext = $abspath" >> $HGRCPATH
$ echo "badext2 =" >> $HGRCPATH
$ hg -q help help
\*\*\* failed to import extension badext from */badext.py: bit bucket overflow (glob)
*** failed to import extension badext2: No module named badext2
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