PETSC_DIR as a symlink

[Jed Brown]

On Thu, 26 Nov 2009 11:15:47 -0600 (CST), Satish Balay <balay at mcs.anl.gov> wrote:
> most of the other packages support multiple install modes.

BTW, I was speaking about libraries that *use* PETSc.  Last time I
checked, it was problematic with Dolfin, Libmesh, and Deal.II.

Jed