* Add NVIDIA Codec support for Windows, Linux and Linux for Tegra
* [ffnvcodec] Fix typos, add/remove comments
* Bump nvcodec version to 9.1.23.1
* Update version number as per change request
* Use PORT variable instead of hardcoded portname
* Identify the release the hash pertains to
* Find nvcodec in 'installed' instead of 'packages'
* Force FFmpeg to look for nvcodec headers in the installed directory instead of /usr/lib/pkgconfig.
* Use p option on cygpath to convert full path in case it contains more than one entry
* Add doxygen to acquired programs
* Add packages option to msys function
* Add documentation for PACKAGES in vcpkg_require_msys
* [ffmpeg][x264] Update to use `PACKAGES` parameter. Tweak docs.
When behind a corporate proxy, one often needs to specify `HTTP_PROXY` and `HTTPS_PROXY` for some command line tools to work properly. However, `pacman` seems to rely on the lowercase equivalent environment variables. In a Windows command prompt environment, it is not possible to set both since Windows environment variables are not case-sensitive. As a workaround, this build script checks for the existence of HTTP_PROXY and HTTPS_PROXY. If they exist, they are exported as lowercase variables.
