Email HTML should be passed in request body not in URI string

[jeffpe]

Ok seems like this was addressed in previous issue from years ago:
https://github.com/Pardot/ruby-pardot/blob/master/lib/pardot/http.rb#L19

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If the html content of an email is passed in the URI string, as the gem does, it is limited in length. The gem will fail when this occurs as it does not recognize the error and generates a NIL Error (undefined method '[]' for nil:nilClass in emails.rb:37 from emails.rb:25 ).

Gem should be altered to pass email html in the body of the http request. Note other parameters could be passed this way as well.

Interestingly the Pardot API does return the error in the return URI string (HTTP 414 URI Too Long ) but the gem does not recognize these errors.

I patched with a few quick conditionals. Looks like better fix was posted.