Close file descriptor after unmounting the FUSE volume
Add support for relative resource paths originating from libosxfuse
Add build parameters

* M_OSXFUSE_ENABLE_KEXT_VERSION_CHECK

  If enabled OSXFUSE will refuse to mount FUSE volumes in case the version o
  the already loaded OSXFUSE kernel extension does not match the version of
  user space library.

* OSXFUSE_MIN_DARWIN_VERSION

  Specifies the minimum supported Darwin version. An error message is displa
  in case OSXFUSE is run on an earlier version.