Investigate speed ups about xerus HOT 2 CLOSED

Regarding the CIF tests:
It seems possible to be able to scrap all the structures tests. The changes in the way the refinement is handled plus the constraints set on COD for now (maximum structure volume), seems to have made things much stabler. The testing might be scraped altogether, which will make Xerus much faster in fast time runs.

Finish branch https://github.com/pedrobcst/Xerus/tree/new_testing (run few more tests with an empty database: Run benchmark with new testing versus old testing)

from xerus.

Regarding simulations:

One way to make things better is for each analysis to only simulate once. Since most of analyze parameters will just be changing the cif dataframe, all the required simulations already exists. Therefore, for subsequent runs tuning the paramaters (ie, delta, g, provider choice etc), we should just use the first run simulation ideally. This might required to rewrite the core of analysis function, but it should be no much work. Will create new issue.

from xerus.