status-change-rfc20-ascii-format-to-standard-00

RFC 20 has status "Unknown" only because it comes from a time that predates both the IETF and our use of the term "standard" (with or without qualifications) to describe Internet technical specifications. RFC 20, which is the best reference for the IETF to use for ASCII format, is clearly an Internet Standard, and this adjusts the historical record by reclassifying RFC 20 as such.