[1.3.X] Fix #15880: Prevent "stalling" when running dev server in background by ignoring SIGTTOU for the duration of tcsetattr.
[1.3.X] Fix #15880: Prevent "stalling" when running dev server in background by ignoring SIGTTOU for the duration of tcsetattr.

Backport of [16326] from trunk.

git-svn-id: 6bee183d120e8e569924b918ee6c564bbb314a32@16327 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django-nonrel/django-nonrel,django-nonrel/django-nonrel,django-nonrel/django-nonrel