Add the `:record_on_server_receive` configuration option (openzipkin#103

)

* Add the `:record_on_server_receive` configuration option

* make config.record_on_server_receive an empty hash by default

* refactor ZipkinTracer::RackHandler#trace_request_information

prevents raising an error if the tracer is not set in Faraday and Exc…

…on (openzipkin#101)

Add tests for response status tracing in Excon middleware (openzipkin…

…#100)

* Add tests for response status tracing

Test the response status is correctly traced.  Also guard against nil
response/status, which might happen if the middleware is inserted into
Excon before the Excon::Middleware::ResponseParser.

* Bump version and add changelog entry

* Simplify response_status method

Add an Excon middleware (openzipkin#97)

* Add Excon middleware tests based on Faraday tests

* Extract middleware shared examples

* Build url using Excon helper instead of URI::Generic

This fixes the case where Excon.new is called with a `query` param that
is a hash instead of a string

* Add specs for query params

* Service name in excon is defaulted to url host

* Remove service name mention

* Allow to pass  a service name

* Lower the required version of Excon

* Bump version and add changelog

* Rescue URI errors

* Make Excon a development dependency

Merge pull request openzipkin#95 from openzipkin/fix_config

fixes sampled_as_boolean configuration

Merge pull request openzipkin#94 from JordiPolo/fix_faraday_setting_ids

fixes faraday middleware and add new convenient classes

Merge pull request openzipkin#90 from openzipkin/limit_required_headers

limits the required zipkin headers to x_b3_trace_id and x_b3_span_id

Merge pull request openzipkin#79 from JordiPolo/feature/support_1_0

adds support for 1/0 as values of the sampled header

Merge pull request openzipkin#85 from blueapron/pass_http_method_to_r…

…ecognize_path

passes the http verb to the recognize_path method

Merge pull request openzipkin#82 from ys/patch-1

Bump the version