planetarium: Cool it with the integration and other declarations.

planetarium: Cool it with the integration and other declarations.

Internal (declare)s are still used, but top-level declarations
(usual-integrations) and (integrate-external) are already made by
compile-file, so are just another barrier to portabimini.

Procedures like project and make-x-rotation-matrix need not be inlined
as they already use flo:vectors to pass 2, 3 and 9 flonums around
efficiently.  Not inlining these reduces matrices.scm to zero
integrable definitions (no .ext file)!