Better comments handling

We've improved the parser to handle comments in a much more intuitive way.

They can now appear also in the middle of control-flow statements such as if, while and so on.
Comment that's trailing an expression/action in the same line will be attached to it rather than to the next line's expression as it was previously.
Invisible comments now follow the same rules as normal comments. It means that the special character '#' can appear in normal text, comments etc.

You can click on the example below to play with it:

Please click on Feedback in the app if you find some cases to be broken.

Happy code2flowing!