Reallocate message type IDs?

[mfoltzgoogle]

The current allocation of message type IDs seems semi random. If I recall there was an attempt to allocate smaller IDs to frequent messages since they may take up less space on the wire. But everything below 63 is one byte.

Here is what I think we should do:

• Reserve 1-63 for anything having to do with media/data frames, presentation connection messages, or other very frequent messages
• Renumber remaining messages in a more logical way, for example always using even numbers for sender => receiver and odd numbers for receiver <= sender and grouping related numbers together