refactor batching
add batching to table.rb
batch class deserves its own file
select class deserves its own file
allow description
batch and select get their own files here too
:lipstick:
move query batches into its own module
move all functionality into QueryBatches module
minor formatting, docs, cleanup
rename Batch to Reader and BatchQuery to QueryReader
clean up the query/query_reader interfaces
Merge pull request #1 from rcarver/razic-batching

Batching cleanup
a spec for QueryBatches module
allow modern rspec mocking
rename QueryReader#each to #read
a spec for QueryReader
resolve duplication of batch specs
spec edge case of results size
improve batch spec for Table#query