Support rest-api with JSON content

[Seddryck]

We should be able to query a rest-api. At the beginning, it should support: GET, HTTP or HTTPS, Json, Anonymous/Basic-Http\Ntml (including current user) and Oauth2 (once access token is received).

<system-under-test>
  <result-set>
    <json-source>
      <rest base-address="https://api.github.com/">
        <authentication>
          <anonymous />
        </authentication>
        <header name="user-agent">nbi</header>
        <path>user/{user}</path>
        <segment name="user">Seddryck</segment>
        <parameter name="order-by">fullName</parameter>
        <parameter name="max_results">10<parameter>
      </rest>
      <json-path>
         ...
      </json-path>
    <json-source>
  </result-set>
<system-under-test>

The preceding rest call should be translated to the following url:
https://api.github.com/users/Seddryck?max_result=10&order-by=fullName

The rest element is returning a string that will be interpreted by the json-path to produce a result-set.

[Seddryck]

Restarted the implementation from scratch.

[Seddryck]

Beta available at https://ci.appveyor.com/project/Seddryck/nbi/builds/28578027/artifacts or 1.22.0-beta0015.