Rewrite of grid submit script in python?

I would like to rewrite the grid submission script for the TDD in python for several reasons:

1. Readability and Maintainability: bash is fairly outdated at this point and most new PhD students will have a hard time modifying the submission script, which wouldn't be the case for python.
2. Managing complexity: the script is complex enough at this point that some proper modularization and avoidance of global variables would be helpful. This however, is hard to achieve in bash.
3. Proper error handling: I had several occasions at this point where the submission script silently fails with either no error or an error that gives me zero information about what happened. While this is also due to missing checks, in python this would be far less of a problem, since we at the very least get a line number and a stacktrace when something goes wrong. An example for this is !810 (merged) where we likely got a silent error due to a shell quoting issue.

The only downsides I see are:

1. It is slightly easier in bash to tie together the somewhat larger number of external program invocations. This is far outweighed by the benefits in my opinion.
2. Rewriting a matured script in python will break things in the beginning, which we have to deal with.

Also this might be a good opportunity to implement #147.

Would people generally be open to a MR with this rewrite? Then I would like to look into this.