Switch Frame Tap v0.6.1 - a 2 MB Windows viewer

A 2 MB Windows download. The Windows viewer zip went from 50 MB to 2 MB.

It shipped the complete FFmpeg libraries (every codec there is), but it only needs the H.264 decoder, the AAC encoder for recordings and the MP4 writer. Those are now built into SwitchFrameTap.exe itself: it's one 3 MB program plus SDL2.dll and libusb-1.0.dll. Decoding is exactly as fast as before; the same FFmpeg version with the same x86 SIMD code.

Updating (Windows): delete the old viewer folder (it had several large avcodec/avformat DLLs) and unzip switch-frame-tap-0.6.1-windows-viewer.zip. The WinUSB driver from Zadig stays; nothing to redo.

Nothing else changed: the Switch side and the Linux viewer are the same as v0.6.0 apart from the version number.