[winswitch] [ANNOUNCE] Xpra 3.0.8: nothing major

[Antoine Martin]

Hi,

There's a fair number of bug fixes in this release, but none of them are
critical.
The clipboard and keyboard (AltGr) handling are the most important ones
in there, the rest is all fairly minor stuff. (platforms, warnings, etc)

Release notes:
* handling of dpi command line switch (correctly this time?)
* bug report window not getting focus on MacOS
* spurious ssh key warnings with newer versions of paramiko
* AltGr mode with non-X11 clients, layout-group changes
* rare unexpected client exit on MS Windows
* MS Windows clipboard:
    update failures
    convert CRLF line endings
* Clipboard:
    fix selection not shown as active in menus (MS Windows and MacOS)
    fix spurious warnings when sharing a session
    fix clipboard reset with python2 builds
    selection translation for outbound data
    support client applications that don't use TARGETS (ie: Motif)
    reject invalid targets
* 'xpra upgrade' wrongly updating non-xpra displays
* logging error in client geometry debugging output
* pulseaudio start command with Ubuntu Xenial
* spurious de-iconifications
* handling of server control commands with python3 clients
* UDP backport bug sending control packets
* vfb getting killed on upgrade failure
* proxy server cleanup: force forwarders to terminate
* session info errors during client exit
* printer cleanup errors with invalid UTF8 printer names
* transient-for popup window workaround
* missing libyuv csc module on MacOS
* unicode errors saving xpra runner shell script with python3
* try to prevent conflicts with Fedora's packages
* better detection of Wayland environments
* use python3 (if installed) by default on Ubuntu Xenial
* don't use Xdummy on arm, too slow
* don't show 'Download' button that we can't honour
* show all pressed keys according to X11 server in 'xpra info'
* try harder not to use video for tiny areas

Cheers,
Antoine