Consider using re-frame's subscription cache in the query parser

[julienfantin]

The parser implementation for re-frame currently uses reagent's make-reaction thus bypassing the re-frame subscription cache.

We could and probably should leverage the cache by automatically registering our subscription handler and instead use re-frame/subscribe in the parser's implementation.

We also currently don't have benchmarks for the re-frame integration and should write those first in order to compare the performance.