Change AnnouncePlayerPlay to announce speed == 0 for pausing slideshow or picture.
renderer: replace render buffer indices with queues
renderer: simplify code by always maintaining one front buffer
renderer: remove now pointless GetNext(Decode/Render) function
renderer: name present buffer structure to be able to reference it
renderer: store bypass format in rendermanager instead

The present method will be overwritten on each flippage
renderer: drop copies of variables, use queue data directly
renderer: grab presentlock in AddVideoPicture
[win32] Enable SSE2 everywhere
[Linux] Read OS information from /etc/os-release
Most modern Linux distributions use the /etc/os-release
file for operating system information.
This patch will try to read the PRETTY_NAME variable from
/etc/os-release to identify the Linux distribution.

If /etc/os-release doesn't exist, the code will still fall back
to lsb_release or the distro-specific release files.

http://www.freedesktop.org/software/systemd/man/os-release.html
http://0pointer.de/blog/projects/os-release.html
removed: BackGroundInfo Loader multithreading (no longer needed)
interfaces: add ILanguageInvoker and ScriptInvocationManager
python: implement CPythonInvoker (replacing XBPyThread)
XBPython: cosmetics
python: let XBPython implement ILanguageInvocationHandler
cosmetics: remove trailing spaces from XBPython.h/cpp
python: register XBPython for .py files
use CScriptInvocationManager instead of XBPython
[win32] update VS project files
changed: Split background info loading into a 2 stages

This allows us to first perform loading of cached (fast) stuff and after that load the lookup (slow) stuff (partially fixes #14071)