match: use util.re.escape instead of re.escape
For a pathological .hgignore with over 2500 glob lines and over 200000 calls to
re.escape, and with re2 available, this speeds up parsing the .hgignore from
0.75 seconds to 0.20 seconds. This causes e.g. 'hg status' with hgwatchman
enabled to go from 1.02 seconds to 0.47 seconds.