beforeSend(oRequest) {
				oRequest.setRequestHeader("X-CSRF-Token", oXcsrfToken);
			}
Sends PUT content request to the back end.

@param {object} oXcsrfToken - Token object
@param {string} sUrl - Request URL
@param {object} oData - Data of PUT request
@param {function} fnResolve - Callback function if request was resolved
@param {function} fnReject - Callback function if request was rejected
@private