Opus approved by the IETF

Three years after we first tried convincing the IETF to standardize an audio codec, Opus has finally been approved by the IETF. The only remaining step until it's officially an RFC is the RFC editor (fixing last minor issues, typos, ...). That should take in the order of 6-8 weeks (variable), at which point we'll have the RFC and the 1.0 release. Thanks to everyone who helped developing, testing, supporting or advocating Opus.