public int intHeader(final String name) throws HttpRequestException {
    return intHeader(name, -1);
  }
Get an integer header from the response falling back to returning -1 if the
header is missing or parsing fails

@param name
@return header value as an integer, -1 when missing or parsing fails
@throws HttpRequestException
lib/src/main/java/com/github/kevinsawicki/http/HttpRequest.java