Fixes #2918 -- Clarified the db_prep_save logic for DateField and DateTimeField to prevent accidental conversion of non-datetime objects into strings, because SQLite doesn't appear to check for valid date format in a string used on an UPDATE of a datetime column.
Fixes #2918 -- Clarified the db_prep_save logic for DateField and DateTimeField to prevent accidental conversion of non-datetime objects into strings, because SQLite doesn't appear to check for valid date format in a string used on an UPDATE of a datetime column.


git-svn-id: 4f9f921b081c523744c7bf24d959a0db39629563@3960 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django-nonrel/django-nonrel,t11e/django,sam-tsai/django-old,skevy/django,Smarsh/django,jamespacileo/django-france,skevy/django,bfirsh/django-old,disqus/django-old,alex/django-old,django-nonrel/django-nonrel,mitsuhiko/django,bfirsh/django-old,Instagram/django,t11e/django,dcramer/django-compositepks,Smarsh/django,bfirsh/django-old,disqus/django-old,sam-tsai/django-old,mitsuhiko/django,hugs/django,alex/django-old,django-nonrel/django-nonrel,hugs/django,alex/django-old,dcramer/django-compositepks,sam-tsai/django-old,sam-tsai/django-old,rawwell/django,disqus/django-old,t11e/django,rawwell/django,skevy/django,hugs/django,Smarsh/django,dcramer/django-compositepks,jamespacileo/django-france,Smarsh/django,jamespacileo/django-france,Instagram/django,Instagram/django,rawwell/django,mitsuhiko/django