Release 0.2.0

[davidpdrsn]

So much good stuff in this release 🥳

---

Added

• builder: Add ServiceBuilderExt which adds methods to tower::ServiceBuilder for
  adding middleware from tower-http (#106)
• request_id: Add SetRequestId and PropagateRequestId middleware (#150)
• trace: Add DefaultMakeSpan::level to make log level of tracing spans easily configurable (#124)
• trace: Add LatencyUnit::Seconds for formatting latencies as seconds (#179)
• trace: Support customizing which status codes are considered failures by GrpcErrorsAsFailures (#189)
• compression: Support specifying predicates to choose when responses should
  be compressed. This can be used to disable compression of small responses,
  responses with a certain content-type, or something user defined (#172)
• fs: Ability to serve precompressed files (#156)
• fs: Support Range requests (#173)
• fs: Properly support HEAD requests which return no body and have the Content-Length header set (#169)

Changed

• AddAuthorization, InFlightRequests, SetRequestHeader,
  SetResponseHeader, AddExtension, MapRequestBody and MapResponseBody
  now requires underlying service to use http::Request<ReqBody> and
  http::Response<ResBody> as request and responses (#182) (BREAKING)
• set_header: Remove unnecessary generic parameter from SetRequestHeaderLayer
  and SetResponseHeaderLayer. This removes the need (and possibility) to specify a
  body type for these layers (#148) (BREAKING)
• compression, decompression: Change the response body error type to
  Box<dyn std::error::Error + Send + Sync>. This makes them usable if
  the body they're wrapping uses Box<dyn std::error::Error + Send + Sync> as
  its error type which they previously weren't (#166) (BREAKING)
• fs: Changed response body type of ServeDir and ServeFile to
  ServeFileSystemResponseBody and ServeFileSystemResponseFuture (#187) (BREAKING)
• auth: Change AuthorizeRequest and AsyncAuthorizeRequest traits to be simpler (#192) (BREAKING)

Removed

• compression, decompression: Remove BodyOrIoError. Its been replaced with Box<dyn std::error::Error + Send + Sync> (#166) (BREAKING)
• compression, decompression: Remove the compression and decompression feature. They were unnecessary
  and compression-full/decompression-full can be used to get full
  compression/decompression support. For more granular control [compression|decompression]-gzip,
  [compression|decompression]-br and [compression|decompression]-deflate may
  be used instead (#170) (BREAKING)

[Nehliin]

🎉

[hawkw]

couple small changelog nits, but 👍