client + server bug squashes, new implementation, and stuff
+ implemented Client.Copy on client and server (not tested)
@ fixed up ChunkPushPullSystem initialization
! fixed variable name crash in ChunkPushPullSystem
! fixed int/float bug in SimpleFS
! fixed bug in SimpleFS.Truncate where master chunk was handled
  as a normal chunk producing a bad file
! added work around for bug in server where block reference count
  is not incrementing and decrementing like it should
+ added code to prevent someone from using block id to gain relative
  file system access