Removing unneeded explicit linking with LLVM libs.

Various improvements for OS X compatibility.

Removing underscore added to C symbols on some platforms (e.g. OSX).

Removing explicit LLVM verison check as it was causing issues on OS X.

Added optimizer.

Merge branch 'feature/string-class' (struct, no methods)

Minor sample update.

Changes to make structs refenece types, fix for increment/decrement code.

Added include guard to oolong-module.h

Created struct for strings, started adapting code.

Allowing external function declarations.

Loading standard library in a more sane way. External functions using naming standard to fully qualify function details.

Including return type in OolongFunction.

Giving Importer and TypeConverter pointers to the context.

Adding license information to souce files and program output.