This is to allow front-end to properly handle ID values.
This change was done to keep consistent with what we were doing
before. Alternative version would be to have a sepparate struct
on the rest package.
We removed handle requirement for all resource like namespace(slug), module, user, page, chart.
Due to that namespace import/export was broken as we were using handle as reference, hence fixed it by replacing handle usage with ID of resource.
It also fixes index of template table for handle column.
