Core: Fix some 64-Bit compiler warnings on MSVC-2010

Nothing special, just to shut the compiler up.
PsychPortAudio: Fix some crash on unload on MS-Windows. Make 64-Bit ready on Windows.

Could happen that during driver shutdown/clear,
PaUtil_SetDebugPrintFunction(NULL) was called to disable debugging
hooks when the actual portaudio.dll wasn't ever delay-loaded ->
undefined entry point -> crash. Check better if plugin is available.

Also add ability to delay-load 64-bit portaudio_x64.dll on 64-Bit
Windows.
Some compiler warning fixes for 64-Bit MSVC 2010 compiles.
InitializePsychSound: Make 64-Bit ready for MS-Windows, some cleanup

Formatting of help text improved. Allow 64-Bit override plugin loading
on MS-Windows.
64-Bit Windows build script: Add PsychPortAudio build setup.

Set it up for 64-Bit Matlab + PsychPortAudio on Windows.
Add dead Eyelink support, with comments about the fact that we can't
support Eyelink for 64-Bit Matlab+Windows, as SR-Research doesn't
provide an Eyelink SDK for 64-Bit Windows.
Rebuild portaudio_x86 plugin for 32-Bit Windows against Win-7 32-Bit SDK.

Just to make sure it works with 32-Bit Windows-7 SDK and MSVC-2010.
Build PsychPortAudio for 64-Bit Matlab on MS-Windows.

Our Portaudio source tree was rebuilt for 32-Bit and 64-Bit MS-Windows
on Windows-7 64-Bit against the Windows-7 platform SDK with Microsoft
Visual C++ 2010 Express Edition.

Relevent MSVC project files and settings were upgraded to work with
this configuration. The files are contained in the
Cohorts/PortAudio/portaudio_msvc2010_buildconfig.zip archive. They'd
need to be copied into the Portaudio/build/msvc/ subfolder of the
portaudio source tree for rebuilding. One would also need the freely
available, but not redistributable, ASIO 2.0 SDK from Steinberg for a
ASIO enabled build, which we can't include into the PTB Git repo,
because it is non redistributable. I can use it locally for binary only
builds, because i have a written license agreement with Steinberg.

Add built portaudio_x64.lib and portaudio_x64.dll with the 64-Bit
Portaudio plugin dll.
Add PsychPortAudio.mexw64 mex file driver for 64-Bit Matlab.
Survived basic testing in a VM so far. The MSVC 2010 compiler threw a
few 64-Bit warnings during the build, but all warnings have been
inspected and verified to be false alerts for our use case, ie., they
are about truncation (possible loss of data) when storing 64-Bit
integers, size_t or pointers in 32-Bit integers. However, wherever that
happens i have verified it will never have any consequences, because
the values assigned are small enough to never even come close to a
32-Bit size limit -- in fact they would easily fit in 16 bit or 8 bit
integers, so no reason to worry about this warnings. The driver build
should be 64-Bit clean, as on the other os platforms.
pnet.mex64 - Rebuild for 64-Bit Matlab+Windows with latest fixes.

Low-Latency improvements, and verify it actually works by checking if
it can run online registration. It does.
moglcore for 64-Bit Matlab on Windows rebuilt.

Update to latest OpenGL extensions.
moalcore for 64-Bit Matlab on Windows rebuilt.
All main mex files for 64-Bit Matlab on MS-Windows rebuilt.

Esp. Screen() to integrate latest improvements.
Also all others just to test build process and for consistency.
Build remaining helper functions for 64-Bit Matlab on Windows.

Move WinJoystickMex.mexw32 to PsychBasic/MatlabWindowsFilesR2007a for
consistency.

Add 64-Bit versions of WinJoystickMex and ShowHideWinTaskBarMex for
Matlab on Windows.

We can't creat a 64-Bit WinTabMex file because the WinTab SDK
apparently doesn't support 64-Bit Windows.

This completes the full set of Mex files for support of 64-Bit Matlab
on MS-Windows.
pnet for 32-Bit Linux Octave + Matlab rebuilt.

Added description of required compiler options to top of pnet.c
Screen: Add caps detection for Gallium LLVMPipe renderer.

VMware's Gallium LLVM-Pipe software rasterizer is slow, but very
capable. Add gfxcaps detection code to detect this backend and expose
its floating point texture+framebuffer support incl. blending and
filtering.
Screen-Linux: Make framerate detection more robust.

Added checks for zero values to avoid floating point exceptions due to
zero divide on invalid values. Make robust against specific weirdness
in video modelines on a Linux VM running inside VirtualBox.
Linux build scripts: Fixups for Ubuntu 12.10 and gcc v4.6+

glibconfg.h header file is in different place, so update include paths
for Screen's glib.
Make sure -std=gnu99 is used for all compiles of at least Screen(), so
OML_sync_control support works.

These problems are new, due to more recent gcc compiler on Ubuntu 12.10.
Linux 32-Bit: Rebuilt almost all mex files + compile fix.

For gcc-4.6+ on Ubuntu 12.10 with -std=gnu99 compile, we need a new
compile fix: char16_t isn't predefined with this compiler config, so
add a hack to define it and avoid compile failure due to unknown
low-level type in typedef. The underlying problem here is that my
prehistoric Matlab 7.4 R2007a no longer really suppports a modern 12.10
system with a gcc version later than 4.2, so dirty hacks are needed to
fix Mathworks compatibility problems: Matlab's matrix.h header file
typedef's mxChar to char16_t, but is not ready for modern compilers
which implement the latest C/C++ standard, where char16_t isn't
predefined.

Almost all mex files for 32-Bit Octave and Matlab rebuilt on Ubuntu
12.10 against gcc-4.7: Exceptions are PsychPortAudio (portaudio lib not
yet installed) and Eyelink (Eyelink-SDK not yet installed). Both are
not a problem, because a rebuilt is not strictly needed -- nothing has
changed since last ptb beta release.

The new char16_t hack in PsychIncludes.h needs testing on the 64-Bit
Linux build system and other platforms though, to make sure it doesn't
interfere with their build / that it is the correct fix for the problem.
Rebuilt Screen for 64-Bit Matlab and Octave on Linux.

To test the updated build script.
PsychPortAudio for 32-Bit Matlab & Octave on Linux rebuilt.

To test updated build scripts.
Disable fileattrib in DownloadPsychtoolbox/SetupPsychtoolbox

Leave it to user to decide if she wants to change file permissions on
the PTB folder.
PsychtoolboxRegistration: Minor code cleanup.