Fix saving of values, had some strings in wrong case.

commerce_omniva.module

@@ -120,8 +120,8 @@ function commerce_omniva_field_settings_form($field, $instance, $has_data) {
  */
 function commerce_omniva_field_validate($entity_type, $entity, $field, $instance, $langcode, $items, &$errors) {
   foreach ($items as $delta => $item) {
-    if (!empty($item['ZIP'])) {
-      if (! is_numeric($item['ZIP'])) {
+    if (!empty($item['zip'])) {
+      if (! is_numeric($item['zip'])) {
         $errors[$field['field_name']][$langcode][$delta][] = array(
           'error' => 'commerce_omniva_invalid',
           'message' => t('You must select a location.'),
@@ -139,7 +139,7 @@ function commerce_omniva_field_validate($entity_type, $entity, $field, $instance
  * the form API flag an error when required fields are empty.
  */
 function commerce_omniva_field_is_empty($item, $field) {
-  return empty($item['ZIP']);
+  return empty($item['zip']);
 }
 
 /**
@@ -174,7 +174,7 @@ function commerce_omniva_field_formatter_view($entity_type, $entity, $field, $in
           '#tag' => 'p',
           '#value' =>
             '<label> ' . $t_name . ':</label> ' .
-            $place[$item['ZIP']]['NAME'],
+            $place[$item['zip']]['NAME'],
         );
       }
       break;
@@ -205,7 +205,7 @@ function commerce_omniva_field_widget_info() {
  *
  */
 function commerce_omniva_field_widget_form(&$form, &$form_state, $field, $instance, $langcode, $items, $delta, $element) {
-  $value = isset($items[$delta]['ZIP']) ? $items[$delta]['ZIP'] : '';
+  $value = isset($items[$delta]['zip']) ? $items[$delta]['zip'] : '';
   $places = commerce_omniva_locations();
   $country = $field['settings']['commerce_omniva_zip_country'];
 
@@ -237,7 +237,7 @@ function commerce_omniva_field_widget_form(&$form, &$form_state, $field, $instan
       break;
   }
 
-  $element['ZIP'] = $widget;
+  $element['zip'] = $widget;
   return $element;
 }