Feature: Easy "shifting" of alphabet/bytes/known alphabet orders etc.

[josh-hemphill]

Describe your feature or enhancement suggestion
While this can technically be accomplished by using the Caesar cipher or modifying the alphabet substitution, it would be nice to either add functionality to the alphabet substituter or add a totally new item that lets you shift alphabets, character sets, or raw bit/byte/hex etc. Also, having preset character sets in their normal order would also save a lot of time.

Describe a concrete use case
Just today, the Break The Code challenge had it's first item be a shift to the dvorak ordered alphabet. It was "d[[;r d yjtf vpgpimfrt" => "apple s third cofounder", which could be achieved with alphabet substitution or the Caesar cipher by putting in the dvorak order of keys in, but it's a bit tedious.