Changes since the last version

[ericprud]

@gkellogg asked for this and it seems especially important given that a proposed definition for extends adds a parameter to satisfies. @gkellogg , have you got a good tool? Diffs like this tend to mangle <pre/>s. Also, I don't know how to point it at e.g. the 2.1 spec and the extends-new-param branch. (The first step is probably to finalize 2.1 and give it a maintenance branch like 2.0.)

Barring a good enough tool, we can do the job a couple times by hand as we finalize 2.2.