Tpetra: Adding (failing) test for Bug #6126

As per Mark's request.
Zoltan2: color_t is now int.
Merge branch 'master' of software.sandia.gov:/space/git/Trilinos
Zoltan2: color_t -> int
MueLu: adding implicit option to RAPScalingTest

Can now run with --implicit (the default) or --explicit.  In implicit
mode, no transpose occurs.  In explicit mode, R is formed by
tranposing P *each* iteration of the RAP kernel.
Zoltan2: Fix bugs in coloring and test. The test passes now.
Zoltan2: Enable coloring test; should pass now.
Zoltan2: Move some arguments to the algorithm constructor.
SEACAS: Fix directory in Trilinos build

a removal of a file had the src/ dir specified twice which doesn't exist so the
file wasn't being removed properly.

(From Sierra)

Build/Test Cases Summary
Enabled Packages: SEACASExodus_for
Disabled Packages: Panzer,PyTrilinos,SEACASExo2mat,SEACASMat2exo,Optika,TrilinosCouplings
Enabled all Forward Packages
0) MPI_DEBUG => Skipped configure, build, test due to no enabled packages! => Does not affect push readiness! (-1.00 min)
1) SERIAL_RELEASE => Skipped configure, build, test due to no enabled packages! => Does not affect push readiness! (-1.00 min)
2) MPI_DEBUG_SS => passed: passed=3,notpassed=0 (1.59 min)
3) SERIAL_RELEASE_SS => passed: passed=5,notpassed=0 (1.81 min)
MueLu: UserAggregation: fixing checks
Tpetra: Removing inner loop ArrayRCPs in Import_Util
Tpetra: Modifying xferAndFillComplete to merge entries.

Needed to get many-to-one correctly.  Especially for Grey's multiply
Revert "Tpetra: Adding (failing) test for Bug #6126"

This reverts commit eda22a258ad3f1273a5b39d3c88b799efe721d29.

Build/Test Cases Summary
Enabled Packages: Tpetra
Enabled all Forward Packages
0) MPI_DEBUG => passed: passed=661,notpassed=0 (64.92 min)
1) SERIAL_RELEASE => passed: passed=585,notpassed=0 (31.60 min)
2) MPI_DEBUG_SS => passed: passed=1057,notpassed=0 (141.25 min)
Other local commits for this build/test group: cbdad10, 15e02a5