Allow stdarg.h to be parsed, at least w/ GNU header files. Variadic functions not yet supported.
Set default log level to INFO if none specified on command line.
Augment smoke test w/ more system header files and the use of 'struct stat'.
Make sure typedefs of fundamental entities exist in the symbol table, but do not result in generating JavaScript typedefs.
Make sure clang predefines are used when parsing header files (so we can use clang header files instead of gcc ones).
Make sure external symbols that code to map depends on are generated in index.js (eg, system types like stat, etc.).
Make sure to differentiate between functions and structs with the same name in symbol table.
Tweak to index.js output generation.
Fix segfault that occurs when referencing same types in includes in different top-level headers (create new CompilerInstance for each file to process).