check domain to prevent updates between domains
add tests
fix tests explicitly
expand on domain test
fix test util to include domain
clean up models
clean up parser
clean up xform
clean up signals
Merge pull request #73 from dimagi/safe-case-update

Safe case update
Merge pull request #74 from dimagi/cleanup

Cleanup
Merge branch 'master' into case_multimedia

Conflicts:
	casexml/apps/case/tests/test_attachments.py
	casexml/apps/case/xform.py
	casexml/apps/case/xml/parser.py