Migrate to Iceweasel 24

Originally created by @intrigeri on #6370 (Redmine)

At the same time as Tails 0.22 is out (December 11, 2013), Firefox 17 will be end-of-life’d, and Firefox 24 will become the new ESR. So, we have to get Iceweasel 24 into Tails 0.22.

Experimental ISO images are available: http://nightly.tails.boum.org/build_Tails_ISO_experimental/

Blueprint: https://tails.boum.org/blueprint/iceweasel_24/

Feature Branch: feature/ff24

Related issues

• Related to #5768 (closed)
• Related to #6371 (closed)
• Related to #6468 (closed)