Configurable option to display footer's content as a right sidebar

[igor-baiborodine]

Implement a configurable option to display the footer's content as a right sidebar. Check Vintage Spirits and Forgotten Cocktails as an example. By default, when displayFooterAsRightSidebar = false, it should be displayed as before. But when displayFooterAsRightSidebar = true, the footer's content should be displayed on the right.

See this discussion for more details.