Reduce response of "add" command correctly
Extract response body for "add" command correctly
Implement "and" boolean reducer
Remove needless method.

Because the message is just for distributor and it has no statusCode
Reduce responses of Groonga commands
Override broadcaster() instead of scatter().

Because Groonga commands uses broadcast_all().
Use Groonga specific collector
Fix typo
Fix typo
Merge result of Groonga commands