Sphinx-autodoc-typehints

- Support and require `nptyping>=2`
- Handle `UnionType`

- Mark it as requiring `nptyping<2`

- Add `typehints_use_rtype` option
- Handles `TypeError` when getting source code via inspect

- Add support for type subscriptions with multiple elements, where one or more elements are tuples; e.g.,
`nptyping.NDArray[(Any, ...), nptyping.Float]`
- Fix bug for arbitrary types accepting singleton subscriptions; e.g., `nptyping.Float[64]`
- Resolve forward references
- Expand and better handle `TypeVar`
- Add intershpinx reference link for `...` to `Ellipsis` (as is just an alias)

- Prevents reaching inner blocks that contains `if TYPE_CHECKING`

- Log a warning instead of crashing when a type guard import fails to resolve
- When resolving type guard imports if the target module does not have source code (such is the case for C-extension
modules) do nothing instead of crashing