Assorted mdadm update to make it work better with systemd

- Assemble-Incremental-don-t-hold-O_EXCL-on-mddev-afte.patch
Ensure fsck/mount don't find an md array to be BUSY
the moment it appears.
- mkinitrd-setup.sh: Make the array device names in
/etc/mdadm.conf in the initrd match those in /etc/mdadm.conf
in the root filesystem. (bnc#851993)

- Restructure-assemble_container_content-and-improve-m.patch
- Incremental-add-export-handling.patch
- udev-rules.degraded
- systemd-mdadm-last-resort@.service
- systemd-mdadm-last-resort@.timer
Teach systemd to start degraded arrays after a timeout if
some missing devices never appear (bnc#832501)
- Incremental-improve-support-for-DEVICE-based-restric.patch
Teach "mdadm --incremental" to handle "DEVICE" lists from
mdadm.conf properly (bnc@851993)