[GSOC-UPDATE](22.08) Impress Remote

Hi everyone,

Bluetooth control on Linux is now working. I'll hopefully be able to 
take a look at Bluetooth on Windows tomorrow. (Any help with Bluetooth 
on mac, i.e. implementation/testing, would be appreciated, but it's 
probably worth waiting until I've tidied the code up a bit to make it 
clearer what exactly has to be platform dependent.)

The new code isn't particularly tidy yet, I'm still sorting out the 
details -- I've also had to somewhat hack my socket buffering to work 
with both osl and C sockets (previously I had a buffer wrapping the 
osl::StreamSocket) -- would it be appropriate to eventually incorporate 
bluetooth sockets into osl? (For Linux the changes would involve adding 
a new Bluetooth protocol to the enum, and making the addresses capable 
of representing bluetooth addresses -- the calls used are just the 
standard socket calls -- I don't know much about Windows or Mac yet. 
Control of other bluetooth functions is all separate from that and done 
via dbus.)

Cheers,

Andrzej