XAMEETINGS-16: Use Google Maps to identify meeting location

You need to check that place is not empty, see 
![empty](https://cloud.githubusercontent.com/assets/629552/4955568/431f0d26-6696-11e4-94a2-051f49cdd260.png)


Also I prefer you do the margins from the CSS ... not using empty lines and 'br's. 

Also I would have like that in Edit mode I have a checkbox saying that I want to display the location on the Map, since users might utilise 'Room Albatross' or 'Room 4423' and these are entities that won't go on a map. WDYT?