af.slidemenu plugin fix for #510

Issue
-
Slide is possible on left when only right menu is enabled, and the other way

Test Case
-
create app with right side menu only and notice that swipe can open left menu

Fix
-
add 2 checks in plugin:
```
if (!$.ui.isSideMenuEnabled() && (dx > startX)) return true;
if (!$.ui.isAsideMenuEnabled() && (dx < startX)) return true;
```