Flask-rebar

-------------------
- Fixes a bug where http 400s are returned as http 500s (99) [Brock
Haywood]

this is for a case where a werkzeug badrequest exception is raised
before the rebar handlers get invoked. this was causing the
default rebar exception handler to run, thus returning a 500
- Updating Contributing page to reflect revised issue review process
(95) [Rick Riensche]
- Fix 96 - Flask no longer treats redirects as errors (97) [Rick
Riensche]

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- Respect user-provided content type in all cases. [Joe Bryan]
- Add default_mimetype to registry. [Joe Bryan]
- Return empty object not empty string, if an empty non-null object
response is specified. [Joe Bryan]

-------------------

Fix
~~~
- DELETE requests should return specified Content-Type (85) [Joe Bryan]

-------------------

Fix
~~~
- Quick rehacktor to unbreak import statements like "from flask_rebar.swagger_generation.swagger_generator import SwaggerV2Generator"
(86) [Rick Riensche]

-------------------
- Add OpenAPI 3 Support (80) [barak]
- Sort required array (81) [Brandon Weng]
- Doc: List Flask-Rebar-Auth0 as an extension (76) [barak]
- Minor changelog manual cleanup. [Rick Riensche]
- Doc: update changelog. [Rick Riensche]

-------------------

Fix
~~~
- Werkzeug 0.14->0.15 introduced some breaking changes in redirects
(73) [Rick Riensche]