log-level context attribute

[lfourie]

This is a proposed metadata attribute (from Context Attribute Backlog):

log-level
Type: String
Description: The level of logging that the publisher may want to log this specific event (e.g. debug)

Assigned to: @vbmade2000

[duglin]

The group closed #63, which was a PR for this issue. Therefore, I believe we can/should close this one too. I'll add it to the list for next week's call, but please add a comment if you think I'm missing something.

[duglin]

Agreed to close on 10/4 call - see previous comment for why

Also, see #227 for the tracing extension that we decided to use instead.