- remove from GS
- remove duplication across Config and ChoicePage
- improve translations (presumably "msdos or gpt" is the most
complicated it will get)
FIXES#1735
Modules nearly always have a Config and either a Job or ViewStep
as their "top level" components. Everything else is implementation-
detail. The *partition* module was unusual in that those two
"top level" components were tucked away in subdirectories.
Shuffle them to the top: this makes it more clear that these
two files are there to coordinate the module.