function getChangeSetResponseIndex(sMimeTypeHeaders) {
		var sContentID = getHeaderValue(sMimeTypeHeaders, "content-id"),
			iResponseIndex;

		if (!sContentID) {
			throw new Error("Content-ID MIME header missing for the change set response.");
		}

		iResponseIndex = parseInt(sContentID);
		if (isNaN(iResponseIndex)) {
			throw new Error("Invalid Content-ID value in change set response.");
		}
		return iResponseIndex;
	}
Returns index of the response inside of a change set by parsing the Content-ID header value
available as a part of the specified change set response <code>sMimeTypeHeaders</code>.
The function expects Content-ID header value to be specified in <code>i.j</code> notation,
where <code>i</code> represents the index of the response inside of the change set.

@param {string} sMimeTypeHeaders
  Section of MIME part representing MIME HTTP headers of the change set response
@returns {number} Zero-based index of the response inside of the change set
@throws {Error} If there is no Content-ID header in the specified
  <code>sMimeTypeHeaders</code> or the available Content-ID header value is not a number.