v0.8.5

• Internal refactorings and optimizations to improve request parsing performance.
  Benchmarks suggest number of requests/s improved by ~30% for common GET requests.
  (#345, #346, #349 and #350 by @clue)

• Add documentation and example for JSON/XML request body and
  improve documentation for concurrency and streaming requests and for error handling.
  (#341 and #342 by @clue)