Fixed extended description toggle for experiences
More condensed headers should also apply to projects
Added spacing under project url
Moved project favicon size declaration to css
Added alt text to web site icon (for good measure)
Apply margin rules for extended description outside of projects

As extended descriptions are now also used elsewhere
Added section borders for better visual separation

Tweaked css naming for extended content, so it makes sense to use the same classes for both extended descriptions in experiences/projects and extended sections (currently: the experience section)