Solaris!

So I decided to run the build and test cases for Solaris today. The results have significantly deteriorated since last time I ran them.

This PR fixes a few issues:
* We should be linking in ```mtmalloc``` for multi-threaded builds on Solaris
* ```regex.h``` and friends are kinda broken/outdated on Solaris, build the bundled version.
* Provide a ```*printf``` implementation that doesn't croak on a ```NULL``` pointer.

The unicode test cases fail as well, will post their results.