preparing for trunk release

Now that we (finally!) got the bug fix release out for, which
I am hoping will be the last, I'd like to turn our attention to a
trunk release, which is where all the good stuff is, including the new
axes grid and mplot3d toolkits.

In advance of this, I suggest you commit any pending work you'd like
to see in the release, and try to tackle any pending sf bug reports or
patches (and file a bug report if you know of an issue that needs to
be addressed). In a week or so, I'll ask Michael to create a release
branch from HEAD at which point the 98.5 branch will die and the
release branch will become the new stable branch to which we apply
only bugfixes and not new features. We'll do a release candidate from
the branch, and then a release, in perhaps two weeks time.