Make some legacy cells conform Reusable & Themable, add some new

Riot/Modules/Common/Cells/TextFieldTableViewCell.swift

@@ -0,0 +1,34 @@
+// 
+// Copyright 2020 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import UIKit
+import Reusable
+
+class TextFieldTableViewCell: UITableViewCell {
+
+    @IBOutlet weak var textField: InsettedTextField!
+    
+}
+
+extension TextFieldTableViewCell: NibReusable {}
+
+extension TextFieldTableViewCell: Themable {
+    
+    func update(theme: Theme) {
+        theme.applyStyle(onTextField: textField)
+    }
+    
+}