Default temp_dir_root fills /tmp

[Former user]

Because temp_dir_root is not specifiable by the user and ignores DIJITSO_CACHE_DIR, numerous calls to dijitso will quickly fill up the /tmp directory. In an HPC environment, this is preventing other users from using /tmp which causes serious knock-on effects. This is occurring in 2019.1.0.

I strongly suggest that temp_dir_root is either abandoned or read from an environment variable. One possible fix would be to replace build.py: Line 120 from: return tempfile.mkdtemp(dir=cache_params["temp_dir_root"]) to: return tempfile.mkdtemp(dir=cache_params["cache_dir"])