[1.2.X] Fixed #15046 -- Added "CHROMEFRAME" as a user agent alias for various...

[1.2.X] Fixed #15046 -- Added "CHROMEFRAME" as a user agent alias for various MSIE fixes. Thanks to chrj for the report and patch.

Backport of r15340 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.2.X@15344 bcc190cf-cafb-0310-a4f2-bffc1f526a37