Otherwise especially looped sounds continue playing while the menu
is open, especially noticeable when opening the menu while firing
the chaingun (the whirring sound continues playing).
OpenAL devices can disconnect, and with some luck they're back after
a few seconds. This especially seems to happen with Intels Windows GPU
driver and display-audio when switching the resolution or enabling
fullscreen, see #209
Now a disconnect is detected and we try to reset the device for 20
seconds, hoping it comes back. This needs at least openal-soft 1.17.0
to build and 1.20.0 or newer to actually work.
Also added missing stub functions in openal_stub.cpp (used by dedicated
server so it doesn't have to link libopenal)
Some functions were duplicated, the only difference was a const in one
parameter. The definitions in the header were with const, so I kept
those versions.
Also, the functions in the header are pure C, so add extern "C",
this fixes issues with MSVC and the formerly duplicated functions.
Don't include the lazy precompiled.h everywhere, only what's
required for the compilation unit.
platform.h needs to be included instead to provide all essential
defines and types.
All includes use the relative path to the neo or the game
specific root.
Move all idlib related includes from idlib/Lib.h to precompiled.h.
precompiled.h still exists for the MFC stuff in tools/.
Add some missing header guards.
