Added Platform.getSystemDPI() API

Author: cmaglie

app/src/processing/app/Theme.java

@@ -122,7 +122,7 @@ static public int getScale() {
         return scale;
     } catch (NumberFormatException ignore) {
     }
-    return 100;
+    return BaseNoGui.getPlatform().getSystemDPI() * 100 / 96;
   }
 
   static public int scale(int size) {

arduino-core/src/processing/app/Platform.java

@@ -333,4 +333,9 @@ public void chmod(File file, int mode) throws IOException, InterruptedException
   public void fixSettingsLocation() throws Exception {
     //noop
   }
+
+  public int getSystemDPI() {
+    return 96;
+  }
+
 }