Log Message:
Update to 1.9.1:

Mercurial 1.9.1 (2011-08-01)

This is a regular bugfix release. It fixes several regressions
introduced in 1.9. The hgweb server now disables MIME type guessing
by default to avoid a potential cross-site scripting issue when
hosting untrusted repositories (issue2923). See UpgradeNotes for
more info.

    dispatch: make sure global options on the command line take precedence
    eol: ignore IOError from deleted files in commitctx
    hgcia: set default value of strip to -1 (issue2891)
    hgweb: do not ignore [auth] if url has a username (issue2822)
    hgweb: handle 'baseurl' configurations with leading slash (issue2934)
    hgweb: raw file mimetype guessing configurable, off by default (BC) (issue2923)
    httpclient: import ca33b88d143c from py-nonblocking-http (issue2932)
    patch: fix parsing patch files containing CRs not followed by LFs
    rebase: block collapse with keepbranches on multiple named branches (issue2112)
    rebase: reset bookmarks (issue2265 and issue2873)
    revert: restore check for uncommitted merge (issue2915) (BC)
    revsets: catch type error on tip^p1(tip) (issue2884)
    revsets: do the right thing with x^:y (issue2884)
    subrepo: handle adding svn subrepo with a svn:external file in it (issue2931)
    subrepo: use working copy of .hgsub to filter status (issue2901)
    url: store and assume the query part of an url is in escaped form (issue2921)
    util: rename the util.localpath that uses url to urllocalpath (issue2875)
    verify: filter messages about missing null manifests (issue2900)
    web: output a correct date in short format (issue2902)