add ficetools, prepro_stages and plot_stages to Fenics_ice

[bearecinos]

Hello @jrmaddison @dngoldberg

I'm putting together the new repo for ASE .. and noticed is silly to have duplicated code. I keep thinking what to do with ficetools, I think is a bit complicated to make it part of Fenics_ice, to me this would imply migrating the pre-processing and the plot_stages folders from the smith_glacier repo to Fenics_ice as ficetools alone makes no sense without the scripts that prepare the input data and plot the output.

I think this would be tricky because we would need to re-design and remove unnecessary code from Fenics_ice e.g. aux and input_data, which we really don't use anymore... as the input_data for the tests is in a different repository.

Of course we will have to make sure ficetools, prepro_stages, and plot_stages are written with a good style standard.

Another idea I had is that we make ficetools a stand alone library. With its own installation, environment and setup.py. Then this could be installed in the environment via pip like I do now with tml_adjoint in the mamba environment.

Then in the new ASE repository we don't need to copy again ficetools, or feed in a sys.path() just import all the other functions

probably we will need to make nice classes so things are more organise

Then the smith repo and the ASE new repo would just hold different ways of creating input data (as each region and scale requires different set up). Maybe this is something to discuss in the meeting