Adding bison/flex build script for compose compiler.

However, when running new version of bison on osx I'm
getting a link error regarding _YYID, need to investigate.
Took out YYID use in our error handling macro.

New version of Bison doesn't define YYID, and we
therefore break on compilation.

However, there are runtime errors with the new
Bison on OSX, and we'll debug this on windows
if indeed there's a good reason to go to the new
version.