- feature requested by GFS2
- adds support for creating shared VGs
- shared LVM setup needs lvmlockd service with dlm lock manager to be running
- to test this change ha_cluster system role is used to set up degenerated cluster on localhost
- the test will be skipped if run locally due to an issue with underlying services
- requires blivet version with shared LVM setup support (storaged-project/blivet#1123)

Older versions of blivet do not support 'shared' parameter. This resulted in
failures in tests unrelated to shared VGs. This change fixes that
behavior as well as fixes minor condition error in a test.