Refactor tests

Use assertIn and assertNotIn where possible.
Use plone.api where possible
Merge branch 'master' into plone-api
Merge branch 'master' into plone-api

Conflicts:
	CHANGES.rst
Revert removal of five.grok from dependencies
Merge remote-tracking branch 'origin/master' into plone-api

Conflicts:
	CHANGES.rst
	src/collective/cover/tests/test_cover.py
	src/collective/cover/upgrades.py
Remove direct dependency on Products.statusmessages
Use api.portal.get_localized_time
Use api.portal.get
Refactor tests

Use plone.api to get views
Merge branch 'master' into plone-api

Conflicts:
	CHANGES.rst
	src/collective/cover/tests/test_basic_tile.py
	src/collective/cover/tests/test_cover.py
	src/collective/cover/tests/test_list_tile.py
Merge branch 'master' into plone-api

Conflicts:
	CHANGES.rst
Use plone.api where possible
Merge branch 'master' into plone-api

Conflicts:
	CHANGES.rst
Refactor SearchItemsBrowserView class

Remove needless initializations and use plone.api.
Merge pull request #345 from collective/plone-api

Use plone.api where possible