Added fm kill --sched (-s) which sends SIGTERM to the fm sched processes on all nodes.  Also made schedulers run in a new process group and kill the entire process group at exit time.  The goal is for kill -s to kill all filemap sched processes and children on the whoel cluster
fix bug in scheduler locking and handling of SIGTERM handler
put tempfiles in a /tmp/fm subdirectory to keep /tmp cleaner
highlight redundant files in plots by default
change fmsync locking behavior for map.  In a first pass, only do work that nobody has started yet.  In a second pass do things that nobody has finished yet.