Add option to disable content encapsulation in response body

[ycintre]

This feature add a config option (dataEncapsulation) to enable/disable content encapsulation in the response body.

The option work like this:

• true (default value) => data encapsulation is enabled (identical to actual behavior) sample body :

  {
  "data": {
  "id": "1",
  "name": "Windstorm"
  }
  }

• false=> data encapsulation is disabled sample body:

  {
  "id": "1",
  "name": "Windstorm"
  }

This closes issue #112

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[ycintre]

I signed it!

[googlebot]

CLAs look good, thanks!

[wardbell]

Hmm. I was resistant at first. But

• it is something that many people have stumbled on over the last few years
• I'm tired of defending the encapsulation; if you want to hang yourself, go ahead
• you've shown that adding this option is easy.

I will have to close this PR because I'm in the middle of adding HttpClient support andI can't take your PR because too much is changing.

But I will offer it in that forthcoming PR #130

[wardbell]

And as of v0.5, "no encapsulation" is the default :-)