Graph500 sequentual and shared-memory reference implementation

See COPYING for the general license.  Portions copyright 2010 by
the Georgia Institute of Technology, and portions copyright 2009-2011
by the Trustees of Indiana University.

The specification is included both in plain text format (Graph500.org,
with Emacs Org mode annotations) and exported HTML (Graph500.html).

Included implementations:
  octave/Graph500.m : GNU Octave (may be Matlab(TM) compatible) from
    the specification.
  seq-list/seq-list : Sequential list-based implementation
  seq-csr/seq-csr : Sequential compressed-sparse-row implementation
  omp-csr/omp-csr : OpenMP compressed-sparse-row implementation
  xmt-csr/xmt-csr : Cray XMT compressed-sparse-row implementation
  xmt-csr-local/xmt-csr-local : Cray XMT compressed-sparse-row
    implementation accumulating vertices into a small buffer before
    storing globally
  mpi/ : Several implementations using MPI

BUILDING INSTRUCTIONS

The Makefile includes make.inc to define compiler and flag variables.
Some sample make.inc files are in the make-incs directory.  The
Makefile relies heavily on implicit rules and is known to work using
GNU Make.

To build the MPI executables, set BUILD_MPI=Yes in your make.inc, and
optionally set MPICC if needed.  There is a separate README file in the mpi/
directory with more information.

To build the OpenMP executables, set BUILD_OPENMP=Yes in your
make.inc, and define CFLAGS_OPENMP appropriately.

For the XMT, ensure the correct modules are loaded and set
BUILD_XMT=Yes.  This disables all other builds, including the
sequential versions.

RUNNING INSTRUCTIONS (OTHER THAN MPI VERSIONS)

Options:
  v   : version
  h|? : this message
  R   : use R-MAT from SSCA2 (default: use Kronecker generator)
  s   : R-MAT scale (default 14)
  e   : R-MAT edge factor (default 16)
  A|a : R-MAT A (default 0.57) >= 0
  B|b : R-MAT B (default 0.19) >= 0
  C|c : R-MAT C (default 0.19) >= 0
  D|d : R-MAT D (default 0.05) >= 0
        Note: Setting 3 of A,B,C,D requires the arguments to sum to
        at most 1.  Otherwise, the parameters are added and normalized
        so that the sum is 1.
  V   : Enable extra (Verbose) output
  o   : Read the edge list from (or dump to) the named file
  r   : Read the BFS roots from (or dump to) the named file

The -o and -r options to the graph500 executable read the data from
binary files that must already match in byte order.  The make-edgelist
executable generates these files given the same options.

Outputs take the form of "key: value", with keys:
  SCALE
  edgefactor
  construction_time
  min_time
  firstquartile_time
  median_time
  thirdquartile_time
  max_time
  mean_time
  stddev_time
  min_nedge
  firstquartile_nedge
  median_nedge
  thirdquartile_nedge
  max_nedge
  mean_nedge
  stddev_nedge
  min_TEPS
  firstquartile_TEPS
  median_TEPS
  thirdquartile_TEPS
  max_TEPS
  harmonic_mean_TEPS
  harmonic_stddev_TEPS