Fixed #14700 - speed up RawQuerySet iterator.
Fixed #14700 - speed up RawQuerySet iterator.

This moves constant work out of the loop, and uses the much faster *args
based model instantiation where possible, to produce very large speed ups.

Thanks to akaariai for the report and patch.

git-svn-id: 554f83ef17aa7291f84efa897c1acfc5d0035373@14692 bcc190cf-cafb-0310-a4f2-bffc1f526a37

svn2github/django,svn2github/django,svn2github/django