Added more Icons: 1256

- appbar_calendar_plus
Added more Icons: 1259

- Added appbar_3d_3ds
- Added appbar_3d_collada
- Added appbar_3d_obj
Added more icons: 1260

- Added appbar_3d_x
fix maximized state path display
Merge pull request #1560 from bitbeans/master

Added more Icons: 1256
upd MahApps.Metro.Resources  to 0.4.0
Merge pull request #1693 from MahApps/1580-maximize-button-display-issue

fix maximized state path display