get data from api, not db
create relations between group and lawsuit
create api to query lawsuits about specific group
refactory createTestRelation to createTestRelationBetween and createTestRelations
add api to get groups of specific category
Merge branch 'views' of https://github.com/yglin/eCourt into views

Conflicts:
	routes/category.js
Merge pull request #23 from yglin/views

Create api, fix test.db bug #19