Remove boasting (especially about performance) from the README
Remove boasting (especially about performance) from the README

Prompted by @rickmed's research into Fluture's current
performance characteristics , I have been running many of the
async performance benchmarking suites available. These tests
indicate that Fluture is certainly fast, but definitely not the
fastest (anymore).

Though my own simple tests using console.time() still seem to
indicate that Fluture is faster than Promises, these more
established tests conclude otherwise. I certainly don't wish
to spread false information, and since it's now uncertain
whether Fluture is actually beneficial to performance, I have
decided to remove these claims from the README and wiki.

Avaq/Fluture,fluture-js/Fluture,fluture-js/Fluture,fluture-js/Fluture