[racket] Racket v5.3.2

>> DrRacket's GUI is more responsive.

Eli, Matt and Robby,

Qualitative comments:

I don't know if change occurred in v5.3.1 or v5.3.2 but DrRacket GUI is now
materially more responsive when editing large racket source code files (~2500
lines).

I thank you very much for the improvement.

I recompiled all my source code under 5.3.2 after midnight and have been running
same in background. No issues to report. Same to slightly faster
(5%-ish)performance relative to v5.3.1. Major garbage collection cycles seem
very fast in both versions. 

I don't have hard data to share, but I think I'm now observing that minor
garbage collection cycles seem to take longer than the major cycles. (is that
even possible?)


R./
Zack