hg.py: add islocal() and defaultdest() functions, refactor
islocal tells if a repo or url is local.
defaultdest returns default path for clone if explicit path not given.
clone can now take repo or url as source
syntax: glob
*.elc
*.orig
*.rej
*~
*.o
*.so
*.pyc
*.swp
*.prof
tests/.coverage*
tests/annotated
tests/*.err
build
contrib/hgsh/hgsh
dist
doc/*.[0-9]
doc/*.[0-9].gendoc.txt
doc/*.[0-9].{x,ht}ml
MANIFEST
patches
mercurial/__version__.py
syntax: regexp
^\.pc/
Output/Mercurial-[0-9.]*.exe