956873: Fix broken rules on older Candlepin servers.

Adding a new java method and then attempting to use it broke all old
servers. Manifest will import but then fail to list pools.

Changed consumer.isManifest() to consumer.getType().isManifest().
Merge pull request #234 from candlepin/dgoodwin/master-ismanifest-fix

956873: Fix broken rules on older Candlepin servers.