This commit also introduces a tempprary fix to an issue where fab is
displayed on wrong screen when switching between bottom tabs rapidly.

call setButtons with empty fab object to remove it

* Implement right SideMenu on Android

* Adapt toggleSideMenu and toggleSideMenuVisible to right SideMenu

When ivoking navigation actions such as push, pop etc, instead of
checking modal visibility, check if modal actually contains the given
navigator. This fix alows to change navigation state in screens while
modal is displayed.