Social Metatags Optimization

Optimization of the Open Graph standards and common meta tags 

<a href="http://mf-geoadmin3.dev.bgdi.ch/ltpoa/">Test here</a>

http://smo.knowem.com/

![capture_after_opti](https://cloud.githubusercontent.com/assets/8614223/4703931/6cea9674-586e-11e4-9f36-e10d0e884b86.PNG)

Logo Geoportal as social image as discussed with @davidoesch