Properly upgrade to FSC 0.0.57
Merge pull request #601 from rojepp/fsc0057_2

Properly upgrade to FSC 0.0.57
Merge branch 'master' into ifilesystem

* master:
  Properly upgrade to FSC 0.0.57
Some cleanup and use ParsedDocument.LastWriteTimeUTC. Still doesn't work.
Keep track of document modified times