bookmarks: abort directly on invalid name
This consolidates the abort message for a bookmark name containing
invalid characters into one place, and renames the valid() method to
checkvalid() to reflect the fact that it's no longer a predicate.
Mercurial
=========
Mercurial is a fast, easy to use, distributed revision control tool
for software developers.
Basic install:
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
Running without installing:
$ make local # build for inplace usage
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See http://mercurial.selenic.com/ for detailed installation
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