Version 0.3.0

• ir::Component takes a has_interface argument and ensures that interface ports are present when it is true.
• The Visitor trait supports new start_context and finish_context methods which allow the pass to affect the context before and after the components are visited respectively.
• New wrap-main pass that generates a top-level main component if the top-level component is not named that.
• Pretty printer prints code more tersely.