.hgignore

Polish patchbomb script.

diffstat output is now a non-default option.

The hgrc file can now contain default information for the patchbomb
script.

Date generation is fixed.

\.orig$
\.rej$
~$
\.so$
\.pyc$
\.swp$
\.prof$
^tests/.*\.err$
^build/
^dist/
^doc/.*\.[0-9](\.(x|ht)ml)?$
^MANIFEST$
^\.pc/
^patches/
^mercurial/__version__.py$