The current `ssl` module has quite a few differences to the CPython
implementation. This change moves the MicroPython variant to a new `tls`
module and provides a wrapper module for `ssl` (in micropython-lib).
Users who only rely on implemented comparible behavior can continue to use
`ssl`, while users that rely on non-compatible behavior should switch to
`tls`. Then we can make the facade in `ssl` more strictly adhere to
CPython.
Signed-off-by: Felix Dörre <felix@dogcraft.de>