Regenerate initrd after configuring keyboard (bnc#888804)

* Some autotranslated code polishing (in a different commit for easier review)
* Update dependency on yast2 >= 3.1.94 (new messages)
I agree, that it might look strange, but for me it is better to have simple
```
allow(Yast::SCR).to receive(:Read).and_call_original
allow(Yast::SCR).to receive(:Write).and_call_original
allow(Yast::SCR).to receive(:Execute).and_call_original
```
after switch of SCR to different root and not need to have specific method for it