Feature: various: remove support for corosync 1 cluster layer

Including:

• configure options: --with-ais, --with-ais-prefix, --with-cman, --with-cs-quorum
• the expected-quorum-votes cluster option
• init script --skip-cman option and ability to manage CMAN and its helpers
• PCMK_STACK and PCMK_uname_is_uuid environment variables
• crm_node -c/--cman and -A/--openais options
• crm_mon -X/--as-xml output will no longer show expected_votes
• crm_report -A/--openais option
• CTSlab.py --ais and --hae options
• cluster-init --cman, -o/--openais, and -p/--plugin options
• the fence_pcmk fence agent
• the pacemaker plugin for corosync 1
• the ability to launch pacemaker-mgmtd
• Public API symbols: CRM_SERVICE, CS_USES_LIBQB, HAVE_CMAP, HAVE_CONFDB, PCMK_SERVICE_ID, SUPPORT_CMAN, SUPPORT_CS_QUORUM, SUPPORT_PLUGIN, XML_ATTR_EXPECTED_VOTES, ais_fd_sync, crm_class_members, crm_class_notify, crm_class_nodeid, crm_class_rmpeer, crm_class_quorum, crm_quorum_cman, pcmk_cluster_classic_ais, pcmk_cluster_cman, is_openais_cluster(), is_classic_ais_cluster(), is_cman_cluster(), crm_node_t born and addr members