wip for case_multimedia for commcarehq main branch and its api usages
WIP for hq to view case attachments. basic script to inject new submissions.
Merge branch 'master' into case_multimedia
Merge branch 'master' into case_multimedia

Conflicts:
	submodules/casexml-src
initial commit for case_attachment multisize handling
case_multimedia catch up merge w/ master
wip for case image and attachment display
adding generic cached url for cached objects
cleaning up abstraction barrier, moving cached_object to dimagi_utils
moving redis requirements to requirements.txt, removing dupe redis req which blew up pip if they were called all together.
cleanup api to do constraints
Merge branch 'master' into case_multimedia

Conflicts:
	corehq/apps/hqwebapp/utils.py
	corehq/apps/reports/standard/domains.py
	corehq/pillows/mappings/domain_mapping.py
	submodules/casexml-src
making comment on script attachment script more descriptive
Merge branch 'master' into case_multimedia

Conflicts:
	submodules/casexml-src
removing stub api_cached_object url and views until they are implemented for reals
cleanup management command
removing bad reference
fixing url reference to use reverse
adding test conditions - wip
finally, getting tests to verify url for attachments working to confirm that url name for attachment retrieval isn't conflicted anywhere