Added a toggle fullscreen button to Maps that is enabled trough the parameter
enablefullscreen=true

Upon receiving the click event, the map container gets the following css styles
set:
  positon: fixed
  top: 0px
  left: 0px
  width: 100%
  height: 100%
  z-index: 10000

which effectively displays the map as fullscreen, overlaying all other
dom elements.

When the button is clicked again, the css styles is reverted to its original
state.

This functionality is only enabled for google maps, however i see no reason
why this should not work with any map service.

Change-Id: Ie019385ee0dd8e62712a42ef5d84e9a1a65d2560