add user settings page
add group
add table migrations
fix group models foreign key error
add settings api
group related models reworked with better logic
integrate group to principal.
add group access permission to principal
models relationship bug fixes

also add smart chart __init__ func
init category config in create_app
resouce restful api simplified.

also add group resouce restful api.
eager relationship loading for chart user/group
add fork and stars api, disable dashboard fork.

dashboard fork in complicate due to the related charts permission
it contains.