Removed some unnecessary classes
Added file chooser dialog and widgets related
Substituted old file chooser with new file chooser
Added editor-android maven profile.

Fixes #285
Removed build from editor-android profile.
Merge pull request #288 from RotaruDan/editorAndroidProfile

Added editor-android maven profile.
Fixing a problem with bad formed json, after recent changes in libgdx
Merge pull request #289 from jtorrente/fix-nonstandardjson-bloodynathan

Fixing a problem with bad formed json, after recent changes in libgdx
- After adding support for C-style comments in their JSON parser, all '/' in string values *must* be properly quoted
- Fixed a bug when saving polygons generated by tracing borders: JSON serializer chokes on Arrays.asList, and requires such lists to be copied over to ArrayLists instead.
Merge pull request #287 from RotaruDan/PaintView

Paint view
Added fileChooserListener to constructor; some javadoc;
Converted fileComparator to private static class
Small bug fix saving FILE_CHOOSER_LAST_FOLDER preference
Efficient rendering of vector-based shapes and lines

- Stages replaced with EditorStage, in charge of a second ShapeRenderer pass
  (similar to the original SpriteBatch pass)
- Actors that wish to draw vector-based in this second pass must implement
  ShapeDrawable
- Replaced all "scaled empty boxes" with a 1 px border rectangle
- Fixes #148 (object-handles resizing themselves)
- Accesses Group's transforms to avoid additional transform matrix creation
Properties renamed to .props to avoid encoding issues
Fixes single hardcoded .properties reference (in I18N)
Fixes a few bad encodings
Merge pull request #292 from manuel-freire/properties-to-props

Properties to props
Actions separated in two packages: model actions and editor actions
Added EditorAction and ModelActions, and associated controllers
Testing invalid arguments in actions
Added default mechanism to validate arguments