* Docs: Getting Started Dependencies
Finally document what one needs to install to use Spack on
Linux and Mac :-)
With <3 for minimal container users and my colleagues with
their fancy Macs.
* Debian Update Packages: GCC, Python
- build-essential: includes gcc, g++ (thx Cory)
- Python: add python3-venv, python3-distutils (thx Pradyun)
* Add RHEL8 Dependencies