Add german format description

[torbencarstens]

some of the questions posed in #1 are answered there

[torbencarstens]

some of the current inconsistencies are correct in the german documentation, e.g. # while this column (8) should be a number by definition, it's usually an underline can be an underline there, but, all other numbers could also be an underscore by the german definition.

there are other inconsistencies as well, the underline field in the gauge number can also be a space by the german definition.

the parser should probably a bit more lax to accommodate both the german and english format description as best as possible (while being able to parse all our actual data).