scm: mercurial: diff '-c' option supports above Mercurial 1.2 (#3724, #7253).
r4662 fails in old Mercurial.
Merged r4683 from trunk (test:scm:setup:mercurial task can be simpler).
Merged r4676 from trunk (change mercurial test repository from tar.gz to bundle).
scm: mercurial: test:scm:setup:mercurial task can be simpler (#7272).
Fixed MailHandler broken by I18n fallback added in r4679.
Fixes fixture added in r4680.
Fixed: wiki pages with cyrillic characters not found with postgresql (#7245).
Adds fallback to 'en' locale for untranslated strings (#5518).
Set the version to stable (#7259).
Make sure en is the current locale when running the test (#7266).