Add option to ignore * and `1 in types

[sobolevn]

There are cases when some types are revealed like:

# N: Revealed type is 'builtins.bool*'

Or like so:

reveal_type(dekind(container))  # N: Revealed type is 'main.IO[def (_ValueType`1) -> _NewValueType`-1]'

Here are the problems with these two things:

1. They can change! Sometimes if you use a different technique inside your type, you will loose this * while everything else will work the exact same way
2. Different versions of python in different environments might produce different numeric results after

`

char in type vars.

So, I propose to add strict: false parameter to our test cases to ignore these chars (and possibly other things in the future).

[sobolevn]

I like strict_assert: false more. And probably we would also need a command line flag: --mypy-strict-assert

[brunns]

PR #55 might cover this use case, though in a different way. Thoughts?