Misc cleanups.
Improve file handling.
Remove VMLISP package.
Turn on prettyprinting for Closure CL.
Silence STYLE-WARNING messages when loading gmp.
Simplify build of Shoe.
Support using gmp with Closure CL.
Rename num-sb.lisp to num-gmp.lisp.
When using sbcl preload "SB-SPROF".