Piro: Revised ObserverBase interface to avoid aliasing

Passed the stamp by value instead of passing it by (const) reference to
avoid potential aliasing, e.g. with the contents of the vector(s) passed
as input arguments.

This is a breaking change that will hopefully not be too disruptive
since no official release of Trilinos has occurred since the
introduction of Piro::ObserverBase.
Piro: Bumped Trilinos release version in doc index
Piro: Revised Provider documentation
Disabling tpetraMapTest; I suspect there isn't a memory leak and Erik is
tired of CDASH messages. :) :)
Changed HAVE_GZIP to ZHAVE_GZIP to remove warnings reported by Roger P.

"I am building an executable that links Trilinos, PETSc, MOOSE, Denovo and
Drekar together.  There is a collision between a petsc define and a zoltan
define.  The warning is below.  You might want to rename the zoltan config
file define from HAVE_GZIP to something like ZOLTAN_HAVE_GZIP just to
namespace protect it against such collisions.  Everything works fine and
compiles, so no need to make a change, but anyone using casl code will see
the build warning below *many* times throughout the moose library build.

Roger

MOOSE Compiling C++ with PCH (in opt mode)
/localhome/p8d/VERA/MOOSEExt/MOOSE/moose/src/constraints/NodeFaceConstraint.C...
In file included from
/localhome/p8d/VERA/Trilinos/packages/zoltan/src/include/zoltan_types.h:82:0,
                 from
/localhome/p8d/VERA/Trilinos/packages/zoltan/src/include/zoltan.h:51,
                 from
/localhome/p8d/VERA/DataTransferKit/src/DTK_RCB.hpp:57,
                 from
/localhome/p8d/VERA/DataTransferKit/src/DTK_PartitionerFactory.hpp:50,
                 from
/localhome/p8d/VERA/DataTransferKit/src/DTK_Rendezvous_def.hpp:52,
                 from
/localhome/p8d/VERA/DataTransferKit/src/DTK_Rendezvous.hpp:223,
                 from
/localhome/p8d/VERA/DataTransferKit/src/DTK_SharedDomainMap_def.hpp:49,
                 from
/localhome/p8d/VERA/DataTransferKit/src/DTK_SharedDomainMap.hpp:209,
                 from
/localhome/p8d/VERA/MOOSEExt/MOOSE/moose/include/transfers/DTKInterpolationHelper.h:31,
                 from
/localhome/p8d/VERA/MOOSEExt/MOOSE/moose/src/transfers/DTKInterpolationHelper.C:27:
/localhome/p8d/BUILD/MPI_RELEASE_SS/Trilinos/packages/zoltan/src/Zoltan_config.h:57:0:
warning: "HAVE_GZIP" redefined [enabled by default]
/projects/TPLs/moose_libs/petsc/petsc-3.3-p4/gcc-opt/include/petscconf.h:401:0:
note: this is the location of the previous definition
"