Http client logging enhancements for mocking

[pikant]

For most of our tests that consume third-party APIs, we use HTTP mocks (e.g.) to speed up the tests. I think this is a fairly common practice.

To speed up the development workflow, it would be very helpful if ray had to following functionality:

1. Ability to only log real HTTP client requests (Real Request: true)
2. Ability to log the raw response body (e.g. JSON) instead of the PHP representation

With these enhancements, one could easily check if all requests were mocked and could quickly add those that were not mocked yet.