Vector: Quick update

I meant to post on my polynomial trick, which now works, but instead got into a long run of small changes this evening. So let me just say that abs has been moved to the setting, so tonight I wrote Vector.abs, which makes Test.pm's is_approx work to compare two Vectors. It feels like Perl 6 is becoming more useful every day.

I also put in a hack workaround for the rakudobug (reported this evening) turned up in t/05-search.t, which means all the Vector tests pass again.

I'm also starting to ponder using SVG to output some NURBS (well, NUBS for now) curves to provide a graphic illustration of what my new code here is doing...