Added ability to use Pact::Term with headers
Merge branch 'master' of github.com:bethesque/pact-mock_service
Reifying the request headers, query and body when serializing pact.
This allows Pact::Term to be used in the request without breaking
verification for non-ruby providers that can't deserialise the Ruby
specific serialisation of Pact::Terms.

eg. {"json_class": "Pact::Term", "data": ...}