[petsc-dev] change coming to master

[Barry Smith]

  I am pushing the branch barry/petscoptions-object in next momentarily.

  This branch changes the API for PetscOptionsGet*() and some related routines to take a new optional first argument of PetscOptions (NULL can be used to get the current behavior). Note that this does not affect the PetscOptionsInt/Read/...() functions because those already take a secret options object.


   Barry