Switch to kde 4.14 and remove 4.12

This sets kde 4.14 as the default kde and removes kde 4.12.

It also removes the package akunambol, which isn't compatible with 4.14, and doesn't seem to be maintained any more.

I've been using 4.14 for a few days, and haven't encountered any problem. All packages that depend on kde have been checked with nox-review, and every one of them build, though I haven't ran them all.

Is there any more worked planned on 4.14 before we make it default?

@iElectric @vcunat @ttuegel