Log Message:
Update mercurial to 0.9.3.

Bug fixes:
 * fix a merge copy/rename corner case
 * fix spurious new heads message with push -r
 * fix hg export %n sequence numbers
 * fix shell quoting on Windows
 * fix charset encoding for hgwebdir and obfuscated addresses
 * fix missing generated files for distribution tarball
 * fix convert-repo tag updates and transcoding of committer
 * add instructions for redoing failed merges

Documentation fixes:
 * hg cat, manifest, and tag default to current parent revision.
 * CGI stub comments clarified
 * corrected synopses for many commands
 * improve doc building and distribution
 * convert-repo: update usage information

Extension fixes:
 * mq: fix strip on Windows
 * mq: fix some guards corner cases
 * gpg: make 'hg sign' default to current parent