The `__virtual__()` function should only return strings on renames.

If the module is not renaming itself, it should simply return True.
Additionally we now also check for different values on `__virtualname__`
and `__virtual__(), these should always match.`
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.
Not renaming, return a boolean in `__virtual__()`.