some Ios7 fixes

* setting edgesForExtendedLayout property in passcode to prevent view from being behind navigation bar (which makes it unusable)
* hiding status bar in login screen and in hybrid applications

(Looking at http://es.slideshare.net/evgenybelyaev16/transition-guide page 17, setting edgesForExtendedLayout should be all that is needed to prevent the status bar from overlapping on the main view but it doesn't seem to work - except in the passcode screen - still investigating).