Simplify coord-rotate
This does not fix the problem that (sin PI) is not really zero because
of the MPU working with higher precision than PI is specified, but at
least it makes the code nicer to read and modify.
http://codereview.appspot.com/263690043
Pases make, make check and a full make doc.
Patch on countdown for October 17th
Patch counted down - please push
Pushed to staging as
commit e860e146ccecf07d42aa53de885916931950245e
Author: David Kastrup dak@gnu.org
Date: Fri Oct 9 16:17:49 2015 +0200