Support Build All Indexes in a bucket or scope in the collection model

Prior to collection, an admin can issue a single BUILD index command to rebuild all defer indexes. BUILD INDEX ON `travel-sample` ((  SELECT RAW name
  FROM system:indexes
  WHERE ..AND state = ‘deferred’ ))

With collections, the BUILD INDEX command can now accept collection name, which means the admin has to submit a BUILD INDEX for each collection.  We should improve this to meet these use cases:

1. Issue a single BUILD index command to rebuild all indexes in the bucket.
2. For a multi-tenanted env, issue a BUILD index for all indexes in a scope.