Add ng-admin js and css
Fix password field display error
Change log4j2 itself log level to INFO.
Fix display error caused by ng-admin
Change first letter to lower case in URL(rest/User --> rest/user)
Move entities application config from EntityService to RestApplication.
Unlink the hierarchy relation between BaseObject and BaseMetaData, change BaseMetaData to singleton.
Add feature to show meta data for an entity, work on #2, remove ng-admin, as it's too "坑爹", no doc at all.