compatable with CoreOS 1688.5.3

Updated to mind mount a tmp directory into the development container since the CoreOS development image doesn't have enough free space to compile ZFS.
corezfs_amd64-usr_1688.5.3_stable.tar.gz

Fixed zfs-overlay.service

Fixed zfs-overlay.service file and updated the way the CoreOS signing key is downloaded.

updated for CoreOS 1520.6.0 and ZoL v0.7.2

v2.0.1

updated for CoreOS 1520.6.0 and ZoL v0.7.2

Complete Rewrite and Update

The script has been rewritten based on a much updated understanding of how Portage works in CoreOS.

v1.2.3

Updated the script for a cleaner separation between building and installing, and cleaned up the way the tarball is packaged.

v1.1.2

Update corezfs

V1.1.1

v1.1.1

Update README.md

v1.1.0

Changed the script to separate the build and install steps so the build output can be copied to, and installed on another machine (with the same CoreOS version) without having to rebuild.

V0.1.1

v0.1.1

Update README.md

v0.1.0

Update README.md