first commit from pi
i forgot committing
add sandbox
check whether or not writing xmp-distribution in module is OK
barrier is needed after reduction
Merge remote branch 'origin/master'

Conflicts:
	sample/graph/mpi.eps
	sample/graph/mpi.sh
	sample/graph/xmp.eps
	sample/graph/xmp.sh
	sample/mpi/a.out
	sample/mpi/go.sh
	sample/mpi/go2.sh
	sample/mpi/go_plot.sh
	sample/mpi/sample.f90
	sample/seq/a.out
	sample/seq/sample.f90
	sample/xmp/a.out
	sample/xmp/go.sh
	sample/xmp/go2.sh
	sample/xmp/go8.sh
	sample/xmp/go_plot.sh
	sample/xmp/sample.f90
	sample/xmp/sample.o
	sample/xmp/sample_size.xmod