Spack upgrades

[lucaparisi91]

We will probably need to upgrade spack multiple times.
We need a process to update spack with minimal damnage to users.

I would propose

• keep the system configuration path outside of tree. Can be set using the environment variable SPACK_SYSTEM_CONFIG_PATH

Requirements

• The config for both user and cse is the same, and should be kept in sync after installation
• All currently installed packages should be available and working before and after the upgrade. This would need a proper testing, but out-of-scope for this issue. ( likely using reframe ) . However some limited basic testing might be in scope

I would setup a script ( python ? ) that automates the deployment of the upgrades.

[lucaparisi91]

The process might involve saving a spack lock file for portably transferring the whole environment.

[welucas2]

v0.23 is out!

[welucas2]

The modules currently activate configs using SPACK_SYSTEM_CONFIG_PATH (see description in the A2 wiki). The repo did not place configs out-of-tree, but you're right, it should and now does, so the next installation would need the locations in the modules to be corrected.

[lucaparisi91]

I am going to go ahead and install v0.23 without upstreaming. I am going to create a separate branch for that installation.

[lucaparisi91]

Pull request in #26.