For events generated by these commands, it may be useful to know details
of the primary node. This makes following additional parameters available
to event notification scripts:
- %p: node ID of the primary
- %a: node name of the primary
- %c: conninfo string for the primary
Implements GitHub #375
The configuration file path is stored to make remote execution of repmgr
(e.g. during "repmgr standby switchover") simpler, so relative paths
make no sense.
Addresses GitHub #332
