KWSys 2015-05-27 (61e0419f)

Extract upstream KWSys using the following shell commands.

$ git archive --prefix=upstream-kwsys/ 61e0419f | tar x
$ git shortlog --no-merges --abbrev=8 --format='%h %s' b1d560a0..61e0419f
Brad King (1):
      61e0419f SystemTools: Teach RemoveFile to tolerate missing file

Matt McCormick (1):
      9a6b7c3f cmake: Set CMP0056 to NEW