Cleanup and... Robustification?

[dbordak]

Hey Revan, finished with those changes I was talking about. Here's what I've got:

• Cleaned up a few comments
• Changed one-line loops into list/dict comprehensions
• Set stdout as default output if none is provided
• Made ingredients into a list (Fixes #3)
• Python 3 compatibility
• Made indented json output an optional feature