Add google maps support, to display the images on Google Maps

[fanningert]

Support over the kirby plugin GMaps. Read the location from the EXIF/XMP attributes and at a google maps over the gallery.

Example:

(image: image.jpg map: true)

or

(image_gallery: * map:true)

Will be display the images like this example: http://www.etechpulse.com/2014/01/styling-infowindow-with-effect-google.html