Merge pull request #168 from amitsedai/7.x-1.x-alpha

Profile picture url fix.
Fixed #137. Added a system 404 page via hook_menu(). Moved the 404 handling mechanism from menu_execute_active_handler() to drupalgap_goto(), then added an invoke all on hook_404.
Added developer friendly alert for renaming 'header' block to 'title'.
Merge branch '7.x-1.x-alpha' of github.com:signalpoint/DrupalGap into 7.x-1.x-alpha
Added drupalgap_form_element_access() and changed _drupalgap_form_render_elements() to check the 'access' property on the form's elements and buttons before rendering them.