Delay the branch for E500 native support

[Jim Blandy]

For what it's worth, I actually like feature-based scheduling, too.
It's inconsistent of me to suggest a delay.

I think my real motivation was just frustration: I've put, what, 45
patches in on this thing so far, and I really wanted to just get it
done.

I don't see any compelling reason to delay the branch.  I'll get
everything onto the trunk, and we can see what people think.