Log Message:
Update to 1.5.2:

This is a monthly bugfix release with numerous minor fixes including:

    * clone: fix URL too long problem with many heads
    * commands: revised documentation of 'default' and 'default-push'
    * convert/cvs: skip bad tags
    * convert/git: check status when reading output stream
    * convert/subversion: fix default URL checker prototype
    * copies: properly visit file context ancestors on working file contexts
    * diffstat: use ui.plain() instead of ui.interactive()
    * dirstate: fix in memory dirstate entries for 1-second race
    * dispatch: don't mangle ImportError abort messages
    * filemerge: use working dir parent as ancestor for backward wdir merge
    * hgrc.5: describe form of config values and mention lists as well
    * hgweb: fix attribute error in error response (issue2060)
    * log: document the new xml style
    * merge: correctly compute the flag for noexec filesystems
    * mq: rewrite strip docstrings
    * mq: use util.unlink instead of os.unlink and os.removedirs
    * patch: don't look for headers in diff lines
    * push: fix bug in warning message selection
    * revlog: fix lazyparser.iter() to return all revisions (issue2137)
    * schemes: fix // breakage with Python 2.6.5 (issue2111)
    * static-http: allow clone -r (issue2164)
    * subrepo: fix repo root path handling in svn subrepo
    * subrepo: propagate and catch push failures
    * templates: document missing template variables
    * util: fix default termwidth() under Windows
    * util: use an explicit prefix for checkexec/checklink temporary files