Inconsistencies with SSE and Layer extensions

[redoPop]

Currently the spec, its examples, and the Medooze reference lib (whep.js) all use different values of rel for the SSE and Layer extensions:

• SSE rel variants:
  • urn:ietf:params:whep:ext:sse (source)
  • urn:ietf:params:whep:ext:core:server-sent-events (source)
  • urn:ietf:params:whip:core:server-sent-events (source)
• Layer rel variants:
  • urn:ietf:params:whep:ext:layer (source)
  • urn:ietf:params:whep:ext:core:layer (source)
  • urn:ietf:params:whip:core:layer (source)

I imagine urn:ietf:params:whep:ext:sse and urn:ietf:params:whep:ext:layer are the intended values, but the ambiguity seems to be causing some fragmentation:

• Dolby is currently using the values that appear in the reference implementation
• Janus' SSE PR (meetecho/simple-whep-server#3) uses the value that appears in the spec's example

We should fix the discrepancy before there's too much fragmentation.

[murillo128]

Thank you for pointing it out, could you double check that everything is consistent?

[redoPop]

Looking good, thank you!