[dfmc-modeling] Clean up whitespace.
[crt] Fix build of things using C-FFI.

Definitions for some primitives for the size_t / ssize_t work were
missing.
[common-dylan] Print function signatures rather than specializers.

This is useful when looking at errors / conditions when they're
displayed.
Merge pull request #805 from waywardmonkeys/improve-method-signature-printing

[common-dylan] Print function signatures rather than specializers.