miniconda-py37 and miniconda-py38

[Predrag Punosevac]

Dear Autonians,

All comp nodes running RHEL 7.8 now have to fully working, up to date
versions of python 3.7.7 and python 3.8.3 installed using miniconda. The
new locations are

/opt/miniconda-py37 and /opt/miniconda-py38

Please adjust your scripts and package locations accordingly before
reporting problems.

Best,
Predrag