allow number type on 'values' argument of 'remove' function
minor fix : add hasRole in Documentation
Added 'roleUsers' function to get users who has a given role.
- new 'roles' bucket will have [roleName] keys to maintain the data.
- addUserRoles, removeUserRoles, removeRole was changed to support this
feature.
Merge pull request #84 from lancers/master

Added 'roleUsers' function to get users who has a given role.