* hacked together tracing fix by wrapping middleware delegate in another delegate
* #227 have re-implemented tracing, cleaned up trace names, probably still need some refactoring and tests as this was a bit of a hack job
* #227 bit of checking for when we dont want to use tracing, also removed a unit test for websockets that wasnt a unit test, i stuck it there because i wanted the code coverage and now im paying the price, will have to work out a better way to do it
* #227 a bit of refactoring to make this work better, still a bit hacky...would like to revisit the whole thing one day
* #227 dont need this
* #227 or this
* #227 small refactor
* #274 added acceptance tests, need to work out failing unit tests but probably going to be a redesign where we hold a reference to the cookie container and empty it if needed
* #274 updated code coverage value
* #274 offloaded cache logic to builder in preparation for adding state
* #274 hacked something together but this is not right approach
* #274 updated defaults and docs
* #274 updated code coverage
* feat： use Https://github.com/ButterflyAPM to monitor each API request monitoring metrics
* feat: using DiagnosticSource and Butterfly.OpenTracing
* refactor：refactor Ocelot tracing， merge code into OcelotDiagnosticListener
* refactor: move OcelotHttpTracingHandler to Requester
* fix： Requester\HttpClientBuilder.cs(10,14): error CS0234: The type or namespace name 'Tracing' does not exist in the namespace
* feat: add test should_set_up_tracing
* feat : Remove extraneous code
* feat: remove unused DiagnosticSource diagnostic
* fix : test UseTracing
* add test should_call_scoped_data_repository_QosProviderError
* add test should_return_any_errors
* add test HttpClientHttpRequesterTest
* it should keep it can not be deleted
