Update libxml2 and libxslt on Windows and switch to new cmake build system #1440

Job	Run time
check-ubuntu (--enable-legacy-features --enable-ftp --enable-http)	4m 48s
check-osx	4m 26s
check-ubuntu	4m 12s
check-ubuntu (--enable-static --enable-static-linking --without-openssl --without-nss --without-g...	1m 16s
check-mingw (MINGW64, x86_64)	16m 51s
check-msvc (mscrypto)	2m 33s
check-msvc (openssl-300)	6m 44s
check-msvc (openssl-300, unicode=no with-dl=no static=yes)	7m 3s
check-mingw (MINGW64, x86_64, --enable-static --enable-static-linking --enable-unicode=no --witho...	6m 50s
check-msvc (mscng, unicode=yes with-dl=yes)	2m 39s
check-msvc (mscng, unicode=no with-dl=no static=yes legacy-features=yes)	2m 53s
check-msvc (mscrypto, unicode=no with-dl=no static=yes legacy-features=yes)	1m 58s
check-ubuntu (--enable-static --enable-static-linking --disable-openssl3-engines --without-nss --...	2m 12s
	1h 4m 25s

Provide feedback