Remove the Addresser type. It isn't really necessary (the Address type
can change between OSes) and makes it difficult to fix a heap allocation
in interrupts (on the Nordic SoftDevices).
This is a backwards incompatible change, but only programs that use
SetConnectHandler should notice this.
There used to be GAP events (connect/disconnect). The main purpose for
these events was to allow applications to re-start advertisement when a
connection was lost - on nrf. Unfortunately things work differently on
Linux, which already has this behavior and for which I haven't yet
implemented these events. Therefore I have removed these events and
instead added code to automatically restart advertisement on connection
loss.
Supporting multiple (incoming) connections as a peripheral would be
useful, but is not currently supported.
