[mb-style] RFC-323: Live Attribute for Performed Relationship Type

[Michael Wiencek]

This RFC is to add a "live" attribute to the recording<->work "performance of"
relationship. It should expire on June 15.

There is a current revision at:
http://wiki.musicbrainz.org/User:Bitmap/Performed_Relationship_Type_Live_Attribute

As you can see, the attribute "indicates that the recording is of a live
performance," and has the following short guideline:

"Use the live attribute when the performance had an audience at the time it
occurred, i.e. it was not prerecorded."

The link phrases should ideally be ordered...
<recording> is a {live} {cover} performance of <work>
<work> has {live} {cover} performance <recording>
And the shorter versions:
{live} {cover} performance of: <work>
{live} {cover} performances: <recordings>

What I also wanted to do was use the date attributes to store the date of the
performance, but perhaps this should be discussed further. If there is wide
agreement to that, I can update the RFC or send a new one.

Michael