[disks] Add file system for logical volumes and boot record

| partition | file system |
|-----------+-------------|
| root      | ext4        |
| swap      | swap        |
| nova      | xfs         |
| glance    | xfs         |
| boot raid | ext2        |
[tests] read_fixture method logs error message
[disks] add ability to define partition in release fixtures
[disks] Fix updating partitions, and size calculation for convertor
[disks] add tests for ceph
Add ceph to redhat fixtures
Disk label support for plain partitions in volume manager
Added Ceph OSD role
Remove Ceph volume definition in Red Hat fixture
Fix flake8 issues
Unit test fixes for Ceph disk tests
More flake8 fixes