Log Message:
v5.8.1
- CI improvements:
  * Add basic working Circle CI v2 config
- Fix URI encoding bug introduced in 39
  * Improve cheroot.test.helper.Controller to properly match unicode

v5.8.0
- CI improvements:
  * Switch to native PyPy support in Travis CI
  * Take into account PEP 257 compliant modules
  * Build wheel in Appveyor and store it as an artifact
- Improve urllib support in ``_compat`` module
- 38 via 39: Improve URI parsing:
  * Make it compliant with RFC 7230, RFC 7231 and RFC 2616
  * Fix setting of ``environ['QUERY_STRING']`` in WSGI
  * Introduce ``proxy_mode`` and ``strict_mode`` argument in ``server.HTTPRequest``
  * Fix decoding of unicode URIs in WSGI 1.0 gateway