Merge branch 'hotfix/0.4.8'

* hotfix/0.4.8:
  don't use disabled class for buttons - it has the attribute
  bump version to 0.4.8
bump version to 0.4.9
use an assets folder external and symlinked resources
Merge branch 'hotfix/0.4.9' into develop

* hotfix/0.4.9:
  use an assets folder external and symlinked resources
  bump version to 0.4.9