Mainly to ignore docstring comments, but also standalone expressions
won't do anything for us either. Raise a warning when a function call
(with no return assigned) is used

Add/test code to incoperate the changes in parser to handle unsafe sets. Need to actually handle the unsafe conditions.

I'm too lazy to split this commit...

The new parser should now work with the simulation backend. Unsafety
checking is added as a frame by frame checking, and doesn't influence
the simulation. Currently only `assert`s in the controller itself is
checked, but other options can be added with ease. When plotted with
plotly, the unsafety set is denoted by segments with a black color

Tested on `demo3` and `ball_bounces_dev` examples

Asserts are embedded into environments and lambdas (so `controller` will
have it too). A `unsafe` function is optionally extracted. Asserts use
`if` conditions as preconditions

All assertions are treated as if they are in the top level (even though
any variables/arguments are still local). If conditions don't affect
anything