Breaking API changes in satori/go.uuid

[iancmcc]

The changes outlined in satori/go.uuid#66 break the btree/immutable package. I guess the changes may or may not be reverted, based on the comments, but a fix might be in order.

[nightrune]

I just hit this as well. I don't need btree yet so its not urgent, but this has been opened for 22 days.

[rsc]

I sent a PR removing go.uuid entirely. It was not contributing much.