[SD-1066] Added aggregations, the new facets
[SD-1066] Added aggregations, the new facets
[SD-1066] fix the category facet
[SD-1066] add aggregates/facets to user content response
[SD-1066] add remove facets they are now replaced by aggregates
Merge remote-tracking branch 'remotes/upstream/master'

Conflicts:
	apps/content.py
	requirements.txt
fix flake errors
fix(requirements): update eve-elastic to 0.1.22
feat(search): set explicit elastic mapping for content

SD-1064
fix(mapping): fix genre ingest to match schema

SD-945
[SD-1066] Added aggregate for urgency
fix(newsml1.2): fix genre parsing to match schema

SD-945
Merge pull request #356 from superdesk/feat-search

search feature