Sanitise generated filenames
Sanitise generated filenames

* wqflask/wqflask/correlation/pre_computes.py: Sanitise the generated
  filenames to get rid of characters that have special meanings in a
  file path, and other characters that are just a nuisance.

genenetwork/genenetwork2,genenetwork/genenetwork2,genenetwork/genenetwork2,genenetwork/genenetwork2