make update quieter when nothing is wrong sometimes when i am going around in my history, i get long lists of errors from the update command. this patch will fix that. i tried to make the code style the same like the rest of the code.

syntax: glob

*.elc
*.orig
*.rej
*~
*.so
*.pyc
*.swp
*.prof
tests/*.err
build
dist
doc/*.[0-9]
doc/*.[0-9].{x,ht}ml
MANIFEST
patches
mercurial/__version__.py

syntax: regexp
^\.pc/