parser.accepts("threads", "number of threads").withRequiredArg().ofType(Integer.class);
parser.accepts("storage-configuration-class",
"[REQUIRED] class of the storage engine configuration to use [e.g. voldemort.store.bdb.BdbStorageConfiguration]")
.withRequiredArg()
.describedAs("class_name");
parser.accepts("props", "Properties file with configuration for the engine")
.withRequiredArg()
.describedAs("config.properties");
parser.accepts("value-size", "The size of the values in the store")
.withRequiredArg()
.describedAs("size")