Add seethroughcloud image
Update Twitter tag for SlipStream in contacts page to #slips3m.

Old: #slipstream.
Add 'print' as Media Type for the CSS.

This allows to use the same CSS when printing the page, so that the printed page has the same look and field as the page on screen.

See http://www.w3schools.com/css/css_mediatypes.asp
Customers background with consistent white border.
Replace home icon with with SixSq logo.
Add SlipStream schema (with smaller logo), SixSq/tasklist#31
Add NuvlaBox schema (with smaller logo), SixSq/tasklist#31
Add Cloud Providers illustration (color and desaturated), SixSq/tasklist#31
Thinner line in Cloud Providers illustration, SixSq/tasklist#31
Re-generate PNGs without white border, SixSq/tasklist#31
Merge branch 'develop' into lou-experiment