Moved make-fringe-from-files and make-fringe-from-file from stp-solve-cluster.rkt to stp-fringefilerep.rkt.
Also changed the fringe-segment creation to have an exists-flag value of 'replace' in distributed-merge-proto-fringe-slices.
added place-holder for path in commented make-fringe-from-file[s]
resolve conflicts from merge savetodisk into this branch