-Disabled button bug fix.
-Button building is updated with checked image option.
-Slider widget mode and slider builder is implemented.
- LoadingWidget fix
Merge pull request #4 from peakgames/LoadingWidgetIssue

- LoadingWidget fix
File.exists() takes too long on Android if the file type is internal.
Merge pull request #2 from peakgames/ButtonModel_Checked

-Disabled button bug fix.
demo xml fix & sysout removed
Merge pull request #5 from peakgames/file_exists

File.exists() takes too long on Android if the file type is internal.
Merge branch 'develop'