match: use self.exact instead of lambda
self.exact uses a set and does not need an extra copy of the files
dirstate: use quicker matchfn() instead of match() everywhere
matchfn does the same as match(), but a direct "link"
alias:
a0104303f400 did not correctly handle whitespace in the args
update --clean: do not unlink added files (
issue575)
templater: lowercase error message
Changing this messages should be safe: automated scripts ought to have
debugged their templates and wont grep for this error message.