Polish translation (#1729)

Translation Credit to: Krzysztof Kucner

Change-Id: I29298525dd017abdf4880e9d2f80a23aa4936a82

appinventor/appengine/src/com/google/appinventor/YaClient.gwt.xml

@@ -133,6 +133,8 @@
   <extend-property name="locale" values="nl"/>
   <!-- German -->
   <extend-property name="locale" values="de"/>
+  <!-- Polish -->
+  <extend-property name="locale" values="pl"/>
 
   <set-property-fallback name="locale" value="en"/>
   <collapse-all-properties/>

appinventor/appengine/src/com/google/appinventor/client/languages.json

@@ -12,5 +12,6 @@
   "pt_BR": "Português do Brasil",
   "pt": "Português",
   "hu": "Magyar",
-  "nl": "Nederlands"
+  "nl": "Nederlands",
+  "pl": "Polski"
 }

appinventor/blocklyeditor/ploverConfig.js

@@ -21,6 +21,7 @@
     '../lib/blockly/msg/js/pt.js',
     '../lib/blockly/msg/js/hu.js',
     '../lib/blockly/msg/js/de.js',
+    '../lib/blockly/msg/js/pl.js',
     // English should always come last as the base language
     '../lib/blockly/msg/js/en.js',
 
@@ -38,6 +39,7 @@
     './src/msg/hu/_messages.js',
     './src/msg/nl/_messages.js',
     './src/msg/de/_messages.js',
+    './src/msg/pl/_messages.js',
     // English should always come last as the base language
     './src/msg/en/_messages.js',
 

appinventor/blocklyeditor/src/language_switch.js

@@ -24,6 +24,7 @@ goog.require('AI.Blockly.Msg.pt');
 goog.require('AI.Blockly.Msg.hu');
 goog.require('AI.Blockly.Msg.nl');
 goog.require('AI.Blockly.Msg.de');
+goog.require('AI.Blockly.Msg.pl');
 
 Blockly.language_switch = {
   // Switch between languages
@@ -84,6 +85,10 @@ Blockly.language_switch = {
         Blockly.Msg.de.switch_blockly_language_to_de.init();
         Blockly.Msg.de.switch_language_to_german.init();
         break;
+      case 'pl':
+        Blockly.Msg.pl.switch_blockly_language_to_pl.init();
+        Blockly.Msg.pl.switch_language_to_polish.init();
+        break;
       case 'en_US':
       case 'en':
       default: