Honeycomb-beeline

Fixed
- Fix missing content_type, content_length, and status_code in spans from error responses (145) [vbarua](https://github.com/vbarua)

Improvements:

- Add app.exception_stacktrace to context when an exception is thrown (135)

 Fixes:

- Fix requests patch to correctly build span name (142)
- Fix deprecations related to unittest usage (141)

- Update Lambda wrapper to allow omission of input/output fields 130 (thank you, fitzoh!)
- Add "request.route" field for Django middleware (thank you, sjoerdjob!)

Improvements:

- Adds support for dataset when parsing honeycomb propagation headers 133

This is a maintenace release to fix a bug in the django middleware that can happen in testing environments when a beeling has
not been initialised.

- Don't attempt to use a non-initialised beeline instance in django middleware 126.
- Adds a .editorconfig to help apply consistent styling across IDEs 127.

Features

We have added new functionality for `http_trace_parse_hook` and `http_trace_propagation_hook`. These hooks allow beeline users
to parse incoming headers, as well as add outgoing headers, allowing for interoperability between Honeycomb,
OpenTelemetry (W3C) and other tracing formats.

- New `beeline` configuration parameters for `http_trace_parse_hook` and `http_trace_propagation_hook`
- New `propagate_and_start_trace` function for use by middleware to invoke the `http_trace_parse_hook`
- New `beeline.propagation` package to centralize propagation-related classes and functions.
- `beeline.propagation.honeycomb` package contains hooks to support parsing and propagation using honeycomb headers.
- `beeline.propagation.w3c` package contains hooks to support parsing and propagation using w3c headers.

Deprecation Notice

- Deprecated the existing `beeline.marshal_trace_context`, and migrated all usage to new
`beeline.propagation.honeycomb` functions. `beeline.marshal_trace_context` will be removed when the next major version of the beeline is released.

Implementation details

- Implemented `beeline.propagation.Request` classes for middleware to aid in support of header and propagation hooks.
- Migrateed existing middleware to use new `beeline.propagation` classes and functions to support `http_trace_parse_hooks`.
- Centralized duplicated code for WSGI variants (Flask, Bottle, Werkzeug) into a single location.
- Added `http_trace_propagation_hook` support to requests and urllib.

Fixes

- Fixed a bug where `urllib.request.urlopen` would fail if given a string URL as an argument.