[Galene] galene.org is now running 0.4

[Juliusz Chroboczek <jch@irif.fr>]

Hi,

After an intense session of testing, I've decided to switch the server
running on galene.org to current master.  I know I shouldn't be deploying
at 3AM, but it's the middle of July, lectures are over, and I really want
this version to get some more testing before September.

(In case you're interested, the testing consisted in running Galene on an
ARM64 board with all but one cores disabled and downclocked to 648MHz.  At
90 flows (10 clients in a single group), it lagged pretty badly, but
didn't lose any video tracks.  Audio is more difficult to verify, of
course.)

The main change in 0.4 is the ability to simulcast and perform scalable
video coding (SVC).  This required using different client-side APIs, and
while I've tried to be careful, I may have broken compatibility with some
browsers.  Since the new features only kick in at three users in a group,
please test either by connecting multiple times to the same group, or by
enabling simulcast manually in the side menu.

In addition, the disk writer has been reworked, and should no longer cause
corruption.

The server now has all the features needed to implement a friendly user
list with user permissions and states ("raise hand").  Unfortunately, we
didn't manage to get around to implementing these features in the default
client; help with this would be appreciated.

Finally, 

-- Juliusz