Add slot to rainbow dependency in preparation of adding a new slot.

(Portage version: 2.2.8-r1/cvs/Linux x86_64, signed Manifest commit with key 0x8883FA56A308A8D7!)
Version bump.

(Portage version: 2.2.8-r1/cvs/Linux x86_64, signed Manifest commit with key 0x8883FA56A308A8D7!)
Version bump to 2.6.0. Needed for some of my tasks. Restrict tests as they fail and upstream does not care much. bug#487216.

(Portage version: 2.2.8-r1/cvs/Linux x86_64, signed Manifest commit with key 8EEE3BE8)
Vesion bump

(Portage version: 2.2.8-r1/cvs/Linux x86_64, signed Manifest commit with key 0xF52D4BBA)