Add 'bootable' checkbox for each disk on UI to not allocate boot partition across all disks

Customer would like to have disks in system that not used by openstack/ceph be untouched.

Real life example (consider this as extend for bug):
In fuel node's disk management section I have partitioned only sda drive. I also have sdb and sdc and leaved them unused because I plan to use them for my own on these servers. Maybe I have a backups/recovery on them or plan to use this SSD drives as b-cache. Whatever. Just leaved them unused in terms of fuel and start the deployment.

Need to add checkbox for each disk, checkboxes will be selected by default.