One warning remains and should be taken care of properly.

In any case: this patch should be reviewed carefully.

- more signed/unsigned
- unused variables
- suggest braces around assignment

This commit wasn't tested (for a lack of tests) but was reviewed and should be safe.

#define'd constants should not end with a semicolon. 

Fix prototypes. C wants void (C++ doesn't need that).

Fix mistaken url for the Sass home page.

lightweight drop-in library.