Multiple coexisting spack installations share the ~/.spack folder. On some occasions, we have seen odd behaviors that currently can be solved by deleting the user ~/.spack folder. However, it will be best if the user could just set in "{SPACK}/etc/spack/defaults/config.yaml" a different path for each spack installation.

Rationale

When a single user manages multiple spack installations there are occasional conflicts due to the shared ~/.spack folder.

Description

Provide a variable in "{SPACK}/etc/spack/defaults/config.yaml" to set a customized path for the ~/.spack folder.