Peter M. Groen / dali-demo

* Added to test Font setting via Property system and system font changes.
* 3 Initial TextLabels;
    first has no font set,
    second is set via the demo json style sheet,
    third is set via the SetProperty in code.
  Only the first should change when the system font changes to a different font
* Pressing button creates a new TextLabel with the system font

Change-Id: I9291797ba357979d9b3d85ab0d3a30a3fbd6c497
Signed-off-by: Agnelo Vaz <agnelo.vaz@samsung.com>