Adds the necessary config entries to ec2.ini, to support ElastiCache replication groups

plugins/inventory/ec2.ini

@@ -65,6 +65,7 @@ all_rds_instances = False
 # By default, only ElastiCache clusters and nodes in the 'available' state
 # are returned. Set 'all_elasticache_clusters' and/or 'all_elastic_nodes'
 # to True return all ElastiCache clusters and nodes, regardless of state.
+all_elasticache_replication_groups = False
 all_elasticache_clusters = False
 all_elasticache_nodes = False
 
@@ -101,6 +102,7 @@ group_by_rds_parameter_group = True
 group_by_elasticache_engine = True
 group_by_elasticache_cluster = True
 group_by_elasticache_parameter_group = True
+group_by_elasticache_replication_group = True
 
 # If you only want to include hosts that match a certain regular expression
 # pattern_include = stage-*