Allow __isnull search.
s/bynary/binary/g
Fix so tests work on Django 1.3.
Add data=None tests.
Merge branch 'wjd-allow_isnull_search' of https://github.com/wdoekes/djorm-ext-pgbytea into wdoekes-wjd-allow_isnull_search

Conflicts:
	djorm_pgbytea/bytea.py