Hi Marcel (and others),

As agreed last week, I've implemented a new D-Bus signal in hcid that 
allows upper-level applications to disconnect gracefuly before the ACL 
connection is terminated as a result of a call to RemoteDeviceDisconnect.

So, this is how it works: when the RemoteDeviceDisconnect is called, we 
send the new signal RemoteDeviceDisconnectionRequested(string bdaddr) 
and wait for 2 seconds before sending the disconnection command to the 
controller.  This enables the service implementations to disconnect in a 
nicer way, as specified in the profile specs (eg. in SIM Access Profile, 
a SIM_DISCONNECT_REQ can be sent by the client).

The change is not very big and should be backwards compatible, except 
for the fact that disconnections will take 2 seconds longer than before.

I also updated the documentation and the apitest script.

Please let me know what you think.

Cheers,
Luca.