Rename/add configuration file options

In previous versions of repmgr, some options had ambiguous meanings,
and/or were used for slightly different purposes. This way we end
up with a couple more options (most of which probably won't need
adjusting) but greater clarity and flexibility.

Removed:

  master_reponse_timeout:
    renamed to "async_query_timeout", as this was its main usage

  retry_promote_interval_secs:
    replaced by "primary_notification_timeout"

Added:
  async_query_timeout:
    timeout (in seconds) when executing asynchronous queries

  primary_notification_timeout:
    number of seconds to wait for notification from the new primary
    after a failover

  primary_follow_timeout:
    number of seconds to wait for the new primary to become available
    when executing "repmgr standby follow"

configfile.h

@@ -78,12 +78,13 @@ typedef struct
 	char		promote_command[MAXLEN];
 	char		follow_command[MAXLEN];
 	int			monitor_interval_secs;
-	int			primary_response_timeout;
 	int			reconnect_attempts;
 	int			reconnect_interval;
-	int			retry_promote_interval_secs;
 	bool		monitoring_history;
 	int			degraded_monitoring_timeout;
+	int			async_query_timeout;
+	int			primary_notification_timeout;
+	int			primary_follow_timeout;
 
 	/* BDR settings */
 	bool		bdr_local_monitoring_only;
@@ -125,10 +126,12 @@ typedef struct
 		/* repmgrd settings */ \
 		FAILOVER_MANUAL, DEFAULT_LOCATION, DEFAULT_PRIORITY, "", "", \
 		DEFAULT_STATS_REPORTING_INTERVAL, \
-		60,	\
 		DEFAULT_RECONNECTION_ATTEMPTS, \
         DEFAULT_RECONNECTION_INTERVAL, \
-        300, false, -1, \
+        false, -1, \
+		DEFAULT_ASYNC_QUERY_TIMEOUT, \
+		DEFAULT_PRIMARY_NOTIFICATION_TIMEOUT,	\
+		DEFAULT_PRIMARY_FOLLOW_TIMEOUT,	\
 		/* BDR settings */ \
 		false, false, \
 		/* service settings */ \