Typing-aliases

Features

- Added `is_sized` and `is_hashable` type guards.

Removals

- Removed `assert_never` as `typing_aliases` provides type aliases along with `typing_extensions`,
and said function should be imported from `typing_extensions` (or `typing`) instead.

Features

- Re-exported `assert_never` from `typing_extensions`.
([15](https://github.com/nekitdev/typing-aliases/pull/15))

- Improved documentation on re-exports.

Features

- Added `StrictPrimitive` and `StrictPayload` (`Primitive` and `Payload` that exclude `None`).

Features

- Added `required` decorator.

Features

- Exported `AnySet[T]`.