Added support for app stylesheets and window mode
Added support for app stylesheets and window mode

To use:

NewApplication();  // defaults to no stylesheet and OPAQUE window

NewApplication("mystylesheet"); // defaults to OPQAUE

NewApplication("mystylesheet", Application.WINDOW_MODE.TRANSPARENT);

NewApplication( Application.WINDOW_MODE.TRANSPARENT); // no style sheet

Change-Id: Ief4755e0892560eb4cba45ebf89a1d8ce103fa34

dalihub/dali-toolkit,dalihub/dali-toolkit,dalihub/dali-toolkit,dalihub/dali-toolkit