Updating Tabs :icon attribute to accept UIImage
Merge pull request #265 from AmoebaConsulting/fix_tab_image_support

Updating Tabs :icon attribute to accept UIImage
support for open(Screen, animated:false) with nav_bar
added functional tests for animation support for navigation controller push
added functional tests for animation support for navigation controller push
added functional tests for animation support for navigation controller push animated
Adding support for open(Screen, animated: false) with specs