Disable panhandler for left swiping if only right sidebar is enabled

[Zazzzles]

First off, nice plugin!

Just a suggestion, if the user does not specify a left or right sidebar the panhandler for swiping gesture still swipes the view in the direction that does not have a sidebar.

I would recommend disabling content swiping in the direction that does not have a sidebar specified.

I think this will greatly improve usability since using a scrollview on a page with a sidebar on it currently leads to very weird swiping behaviour on the x-axis in both directions even though there is only a sidebar on one side of the view.