gcsfuse v0.12.0

• We no longer distribute tarballs containing pre-built binaries. Please use
  the .rpm or .deb files on Linux, homebrew on OS X, or install from source.
• Rate limiting should be more accurate, and should be less restrictive when
  the file system has just been mounted. See commit 5fb47e0.
• The --file-mode and --dir-mode flags now accept their arguments in
  octal, matching tools like chmod.
• There is no longer a helper bash script installed into /sbin; rather the
  mount_gcsfuse program (mount.gcsfuse on Linux) is installed directly.
• mount_gcsfuse now performs its own daemonization, and doesn't require a
  tool like daemon to be installed.
• mount now waits for the file system to be mounted, and returns an
  appropriate exit code.
• Copying files and directories with the Finder on OS X now works better. See
  issue #125.