[X] New PETSc version installation instructions + automated install on Phoenix
Will include Phoenix CI in next PR to prove the scripts can successfully install everything, but I can do that in this PR if necessary.
Still working on ICE build. It uses a custom install script because I'm not sure how else to handle the different module names on the cluster. Should be able to include it in next PR too.
Not sure if changes in PR #2 will work with this petsc version, but I guess whoever does that ticket can see.
[X] Makefile for if user wants to use lapack/blas for petsc instead of mkl