Fix for issue [#1351350]

Fix for issue [#1579966]

Added default bottom margin to avoid overlaps on the default navigation and content below the flex slider widget

Fixed nav layering
Added flex-nav-container element per the demo on flex slider homepage

Added typecasting on saved values for option sets

Adjusted naming of Flex Slider
Switched flexslider_views_slideshow to load flexslider_add() instead of drupal_add_library('flexslider', 'flexslider');