Add compiled .so caching to Chicken support
Add compiled .so caching to Chicken support

- Now give compile-file a reasonable destination for the output
- Check for aforementioned output and skip the compile if exists
- None of the above happens if the system-type is 'windows-nt,
  which may not be a necessary restriction. And, the existing
  geiser-chicken-compile-geiser-p var applies.

Resolves jaor/geiser#73 for non-windows system

ChaosEternal/geiser