[1.1.X] Added backwards incompatibility note to 1.1.2 release notes for the...

[1.1.X] Added backwards incompatibility note to 1.1.2 release notes for the change in test runner exit status codes (refs #11615).

Backport of r12070 from trunk.


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@12071 bcc190cf-cafb-0310-a4f2-bffc1f526a37