Initial work on /query for multigets

Initial work to implement multi-gets via a POST request with JSON payload.

See mget-example.json for the proposed payload format for specifying multi-gets.
Remove debug println
Rename routes to /multi
Split multi-functions into separate protocol

Adds basic implementations for mset and mdelete
Add more examples for mget payloads
Flatten this file
Move multi POST (mget) examples to better spot

Will want to provide PUT examples
Use :modified_at for consistency

It looks like get* used :modified_at and set* used :modified.

Update set* since the column is named :modified_at

/cc @drsnyder
Implement naïve mset handler

Does sequential calls to set*
Includes example payload
Add help info about the multi interface
Implement multi DELETE with 501 "Not Implemented" response
Do single-query mset

/cc @drsnyder
Bump minor version for new functionality
Merge branch 'master' of github.com:drsnyder/poky into multi-get-queries

Conflicts:
	src/poky/protocol/http.clj
Record /multi traffic in new-relic
Add /kv prefix, leave off category
Adds tests for jdbc's mget, mset
Prevent empty conditions from forming query

return empty collection from mget for edge cases of conds such as [{}]
Add integration tests for mget and mset
Add more multi examples