Remove `input` from warnings

Took me some time to figure out where the big message on console was coming from. And it isn't even a warning :/

I think you guys should consider removing this: https://github.com/danielgtaylor/aglio/blob/master/src/main.coffee#L119

Or changing the examples on the readme. I still don't know what a real `warnings` array would look like.

Start with src/main.coffee at the linked line and reproduce the console message described in the issue. Compare the output with the README examples and determine whether the input entry should be absent from warnings or documented differently. Done means the console output and examples no longer misrepresent input as a warning.

Written by the indexing model from the issue text.