ChangeLog, pass3.c, problem.c, problem.h, util.c:

ChangeLog, pass3.c, problem.c, problem.h, util.c:
  util.c (print_resource_track): Use mallinfo if present to get more
  	accurate malloc statistics.
  pass3.c (get_lost_and_found): Check to see if lost+found is a plain
  	fail; if so, offer to unlink it.
  problem.c, problem.h (PR_3_LPF_NOTDIR): Add new problem code.
  problem.c: Fix problem message for PR_1_BAD_GROUP_DESCRIPTORS so that
  	the block group number is printed.  Add new prompt, PROMPT_UNLINK.