utils_cluster: cluster_pcs_1_2 utilizing patch-level granularity

... in tracked Pacemaker versions

Signed-off-by: Jan Pokorný <jpokorny@redhat.com>
tests/utils_cluster: add test_cluster_pcs_1_2

Signed-off-by: Jan Pokorný <jpokorny@redhat.com>
filters/ccsflat2pcsprelude[cluster]: comment wrt. minimal config

Signed-off-by: Jan Pokorný <jpokorny@redhat.com>
utils_cluster: update knowledge about el6.6

Signed-off-by: Jan Pokorný <jpokorny@redhat.com>
commands/ccs2pcs: use cluster_pcs_1_2 to produce a warning

... if suitable

Signed-off-by: Jan Pokorný <jpokorny@redhat.com>