Update py-mercurial to 3.7.2.

Include
changeset:  34663:332926212ef8
user:        FUJIWARA Katsunori <foozy@lares.dti.ne.jp>
date:        Wed Feb 24 06:10:46 2016 +0900
files:      mercurial/repoview.py tests/test-commandserver.t
description:
repoview: discard filtered changelog if index isn't shared with unfiltered

on top of 3.7.2 to fix a test failure, see
https://bz.mercurial-scm.org/show_bug.cgi?id=4642

This is a regularly-scheduled bugfix release.

    bundlerepo: properly handle hidden linkrev in filelog (issue4945)
    bundlerepo: properly handle hidden linkrev in manifestlog (issue4945)
    demandimport: add _imp to ignore list
    doc: correct example concerning "hg purge" alias in man page "hgrc.5"
    doc: remove deprecated option from synopsis of command help
    fileset: fix copy/paste in eol() error message
    help: fix typo in backgroundclose documentation
    help: hg.intevation.de is new primary name of hg.intevation.de (and new cert)
    help: update template examples to use reST literal syntax
    hg: obtain lock when creating share from pooled repo (issue5104)
    log: fix order of revisions filtered by multiple OR options (issue5100)
    rebase: update working directory when aborting (issue5084)
    revert: properly revert to ancestor of p2 during merge (issue5052)
    revset: flatten chained 'list' operations (aka function args) (issue5072)
    setup: avoid procedure related to hg.exe at setup.py --pure
    ui: fix crash by non-interactive prompt echo for user name
    unionrepo: properly handle hidden linkrev in revlog (issue5070)
    zeroconf: forward all arguments passed to ui.configitems() wrapper

(wiz)