//  "key agreement",
  //  "data encipherment",
  //  "cert sign",
  //  "crl sign",
  //  "encipher only",
  //  "decipher only",
  //  "any",
  //  "server auth",
  //  "client auth",
  //  "code signing",
  //  "email protection",
  //  "s/mime",
  //  "ipsec end system",
  //  "ipsec tunnel",
  //  "ipsec user",
  //  "timestamping",
  //  "ocsp signing",
  //  "microsoft sgc",

// but will be re-emitted in their canonical form. (So always use canonical
// form, or don't diff.)
//
// This format is intended to make it difficult to use these numbers without
// writing some sort of special handling code in the hopes that that will
// cause implementors to also use a fixed point implementation.
//
// +protobuf=true
// +protobuf.embed=string
// +protobuf.options.marshal=false