Unfortunately, these timeouts are the only realiable way (for now), to
be able to detect broken connections due to half-open sockets. Such a
thing occurs when getting out of the WiFi coverage area or when
disconnecting from the AP (sometimes the client doesn't send the
disconnect packet).
I2C objects can be freed by the GC and a __del__ method is provided
in order to de-init the peripheral prior to being garbage collected.
UART objects are now added to a local list and this list is now part
of the VM_STATE.
