Fixed #11907 -- EmailField now runs strip() on its input. This means...

Fixed #11907 -- EmailField now runs strip() on its input. This means mistakenly including leading or trailing spaces will not cause a validation error, and clean() will remove those spaces. Thanks, krisneuharth, djansoft and SmileyChris

git-svn-id: http://code.djangoproject.com/svn/django/trunk@13997 bcc190cf-cafb-0310-a4f2-bffc1f526a37