[zeroibis]

Update released, anyone have any issues with it?

Changes below:
- Added mat_viewportupscale and mat_viewportscale to enable rendering the world at a reduced resolution
- "mat_viewportupscale 1" and "mat_viewportscale 0.5" will downscale world rendering by 50%
- Added positional audio support for Mumble clients
- Added a new ConVar mp_mapcycle_empty_timeout_seconds to trigger a changelevel when the server is empty
- Added a new ConVar sv_shutdown_timeout_minutes
- Forces a server to shutdown if it has been requested to do so, even if the server is not empty
- Fixed a ConVar exploit that allowed malformed values to circumvent range checks
- Fixed a con_logfile ConVar exploit
- Fixed HTTP downloads on Mac not sending an HTTP referer
- Fixed a bug that prevented consecutive clicks on scrollbar buttons
- Fixed a bug that was causing intermittent lag spikes for Linux dedicated servers
- Fixed a crash while command-tabbing on Mac in fullscreen
- Fixed a client crash in the sound emitter
- Fixed an audio problem for Mac users
- Fixed MOTD sometimes not displaying HTML contents
- Improved the performance and stability of the libraries used for in-game HTML display
- Performance and stability improvements
- Updated to support Big Picture mode