DOE-2 support

[mitchpaulus]

Add DOE-2 Support

Important notes for DOE-2 support:

• Semantic predicates were added to the Lexer. This means that the parser remains exactly the same between Idfs and Bdls as the target languages.
• New command line arguments were added for testing purposes since the normal grun only works with Java.
• Pretty much everywhere now needs to know whether we are targeting EnergyPlus or DOE-2. You'll see that parameter passed in to Lexers, Visitors, and Listeners.
• This changed the grammar compilation to put files directly into the src directory. Previously was a symlink, but editors like Rider did not like that much.