[1.0.X] Fixed #9212: Added code to check the xgettext version, and if it is...

[1.0.X] Fixed #9212: Added code to check the xgettext version, and if it is lower than 0.15, undo an incorrect encoding to utf-8 done by xgettext.  This bug was fixed in xgettext 0.15, but the most-easily-installed Windows gettext binaries are older (0.13.1), so we work around it.

Backport of r9155 from trunk.


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.0.X@9156 bcc190cf-cafb-0310-a4f2-bffc1f526a37