static _serializeNumericStringArray(form, serializedSpaceCharacter = '+') {
        return this._serialize(form, true, 'unformatted', serializedSpaceCharacter);
    }
Generate an Array with the form values, outputting numeric strings for each AutoNumeric-managed element values.

@param {HTMLFormElement} form
@param {string} serializedSpaceCharacter
@returns {Array}