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)
better use `Mode.SetMode("installation")` https://github.com/yast/yast-yast2/blob/69387ac3e5d13508d2b094f0dfbf9af1a5df0d78/library/general/src/modules/Mode.rb#L165