add support for HasManyDeep/belongs-to-through

[PhHitachi]

package: https://github.com/staudenmeir/

Hi, i have a problem here when displaying record with deep relationship.

Company -> Branch -> department -> employee/users

i'm trying to get all associates employee for the current user/admin with different branches with specific company

Company
 - id
 - name

Branch
 - id
 - company_id
 - name

Department
 - id
 - branch_id
 - name

Users
 - id
 - department_id
 - name

public function index(Builder $dataTable)
   {
       if (request()->ajax()) {
           return DataTables::of(auth()->user()->company()->with('employees'))
           ->editColumn('created_at', function ($user) {
               return $user->created_at->format('F j, Y, g:i a');
           })
           ->toJson();
       }

       $html = $dataTable->columns([
           [
               'title' => 'Employee ID',
               'data' => 'employees.id', 
               'className' => ''
           ],
           [
               'title' => 'Date',
               'data' => 'employees.created_at', 
               'className' => ''
           ],
       ]);

       return view('employee.index', [
           'dataTable' => $html,
       ]);
   }
}

Output:

{
   "draw":1,
   "recordsTotal":1,
   "recordsFiltered":0,
   "data":[],
   "error":"Exception Message:\n\nRelation Staudenmeir\\EloquentHasManyDeep\\HasManyDeep is not yet supported."
}