Fix clusterstart failure in gpsegwalrep.py
Fix clusterstart failure in gpsegwalrep.py

Also support start master in utility_mode properly to avoid FTS getting
started under master-only utility mode, which gave the following error
message:

```
"ERROR","22000","Greenplum Database number of segments inconsistency: count is 1 from pg_catalog.gp_id table, but 3 from getCdbComponentDatabases()",,,,,,,0,,"cdbutil.c",340,
```

Signed-off-by: Xin Zhang <80ac6425c128040c27b3c6077c824bc26222f5e7@pivotal.io>
Signed-off-by: Asim R P <24f343109504afa210657d296a0873118cbd2b97@pivotal.io>

yuanzhao/gpdb,edespino/gpdb,Chibin/gpdb,edespino/gpdb,jmcatamney/gpdb,lisakowen/gpdb,50wu/gpdb,adam8157/gpdb,lisakowen/gpdb,yuanzhao/gpdb,xinzweb/gpdb,adam8157/gpdb,xinzweb/gpdb,xinzweb/gpdb,greenplum-db/gpdb,jmcatamney/gpdb,yuanzhao/gpdb,Chibin/gpdb,edespino/gpdb,Chibin/gpdb,ashwinstar/gpdb,edespino/gpdb,lisakowen/gpdb,50wu/gpdb,greenplum-db/gpdb,lisakowen/gpdb,Chibin/gpdb,greenplum-db/gpdb,Chibin/gpdb,lisakowen/gpdb,lisakowen/gpdb,greenplum-db/gpdb,edespino/gpdb,edespino/gpdb,jmcatamney/gpdb,xinzweb/gpdb,Chibin/gpdb,xinzweb/gpdb,ashwinstar/gpdb,50wu/gpdb,edespino/gpdb,edespino/gpdb,jmcatamney/gpdb,adam8157/gpdb,ashwinstar/gpdb,adam8157/gpdb,ashwinstar/gpdb,edespino/gpdb,50wu/gpdb,Chibin/gpdb,Chibin/gpdb,greenplum-db/gpdb,xinzweb/gpdb,jmcatamney/gpdb,adam8157/gpdb,lisakowen/gpdb,edespino/gpdb,50wu/gpdb,adam8157/gpdb,jmcatamney/gpdb,yuanzhao/gpdb,50wu/gpdb,adam8157/gpdb,ashwinstar/gpdb,greenplum-db/gpdb,yuanzhao/gpdb,ashwinstar/gpdb,Chibin/gpdb,yuanzhao/gpdb,Chibin/gpdb,50wu/gpdb,lisakowen/gpdb,50wu/gpdb,greenplum-db/gpdb,adam8157/gpdb,jmcatamney/gpdb,yuanzhao/gpdb,xinzweb/gpdb,ashwinstar/gpdb,ashwinstar/gpdb,yuanzhao/gpdb,yuanzhao/gpdb,greenplum-db/gpdb,xinzweb/gpdb,jmcatamney/gpdb,yuanzhao/gpdb