Form editor

- new/edit in forms listing goes to editor
- fixed editor dependencies (via Webpack)
- updated forms table schema
- saving/loading a form works

lib/Form/Block/Checkbox.php

@@ -0,0 +1,43 @@
+<?php
+namespace MailPoet\Form\Block;
+
+class Checkbox extends Base {
+
+  static function render($block) {
+    $html = '';
+
+    $field_name = static::getFieldName($block);
+    $field_validation = static::getInputValidation($block);
+
+    // TODO: check if it still makes sense
+    // create hidden default value
+    // $html .= '<input type="hidden"name="'.$field_name.'" value="0" '.static::getInputValidation($block).'/>';
+
+    $html .= '<p class="mailpoet_paragraph">';
+
+    $html .= static::renderLabel($block);
+
+    foreach($block['params']['values'] as $option) {
+      $html .= '<label class="mailpoet_checkbox_label">';
+
+      $html .= '<input type="checkbox" class="mailpoet_checkbox" ';
+
+      $html .= 'name="'.$field_name.'" ';
+
+      $html .= 'value="1" ';
+
+      $html .= (isset($option['is_checked']) && $option['is_checked'])
+                ? 'checked="checked"' : '';
+      $html .= $field_validation;
+
+      $html .= ' />'.$option['value'];
+
+      $html .= '</label>';
+    }
+
+    $html .= '</p>';
+
+    return $html;
+  }
+}
+