test category using global data
add api to add a particular event to a particular category.
reorg test story description
get cause just only a particular event to avoid duplicate cause title problem
add api to list events for a particular category
rename getEventByTitle to getEvent
reorg sturcture
add api to create cause for a particular event
add api to get cause of a particular event
add api to list causes of a event
update test description
change test order, create association than query
add api to create group
add api to add group to event
add api to get group
add api to create new law