Adds a videos page

With all the existing screencast embedded.
Links from the footer.
Updated the 3.0.0/features page with the new videos.
Removes the version number in the pages title
Added Retina Display to the FAQ.
Added section about running tests inside Eclipse, on the Setup page.

The well-kept secret of adding `-Dsdtcore.headless` and `-Dsdtcore.notimeouts` is
no longer a secret!
Merge pull request #51 from huitseeker/maintenance/release-upgrade

Additions to the Documentation tied to the 3.0.0 release.
Folded
https://www.assembla.com/spaces/scala-ide/wiki/Setup
into
current-user-doc/advancedsetup/index.html

Folded
http://scala-ide.org/docs/dev/appendix/scala-compiler-dev-with-eclipse.htmlhttp://scala-ide.org/docs/dev/appendix/scala-compiler-dev-with-eclipse.html
into:
tutorials/scalac-trunk/index.html

This fixes https://github.com/scala-ide/scala-ide.github.com/issues/26
Continuations being enabled by default was reverted in https://github.com/scala/scala/commit/39a88f5680

This fixes #34.
Added mention of the tasks list and the outline view.

Closes #6, #8.
Added mention of Inferred type hover.
This closes #3.
Moved shortcuts to a centralized location.

removed unjustified new tags as per PR comments

Linked to hover typing from structured selection

Modifications after PR review. Thanks @dotta !