function getFontFamily(fontInfo, ttf, opts) {
    var fontFamily = opts.fontFamily;
    // Call transform function
    if (typeof fontFamily === 'function') {
        fontFamily = fontFamily(_.cloneDeep(fontInfo), ttf);
    }
    return fontFamily || ttf.name.fontFamily || fontInfo.fontFile;
}
get font family name

@param {Object} fontInfo font info object
@param {ttfObject} ttf ttfObject
@param {Object} opts opts
@return {string} font family name