RancherOS v0.9.0

Schedule

2017-3-8 - https://github.com/rancher/os/milestone/20

Release goals

• simplify and stabelise non-persistent use - like PXE boot - and cloud-config use
• Invalid cloud-init datasource URL causes boot process to hang forever #1538
• Support merging of multiple cloud-init datasources #1536
• Kernel parameters (e.g. rancher.password) are readable by any user-docker container #1537
• Decouple kernel files from the OS files, so we can update them independently (kernel modules/headers/extras extracted into their own initrd, so we can mix&match)
• Rancher server service #82
• Raid installer and update?