Fixed pip_update
Fixed serializers errors and warnings
Refactor all uuid usage into id;
Changed API_INDEX to new base url
Fixed ToolDetailView.get_template_names' template path
Fixed SheetItem.has_comments to also check for self.discussion.exists()
Merge branch 'develop' of https://github.com/prjts/open-budgets into develop

Conflicts:
	fabfile/local.py