Restrict API ranges for each VSScript library loading method

Fix typo

Fix loading old VS from library list

Installer: do not write anything to registry

Update BUILDING: should set VS_INCLUDE_PATH before Makefile creation

Loading vsscript by env python3

Update build instructions

Change the way VS header files are included

Change vsscript library name

Revert "Include VapourSynth headers (VS 4.2, VSS 4.3)"

Update texts

Load vsscript from new places since R74

Include VapourSynth headers (VS 4.2, VSS 4.3)

Switch to Qt6 regex

Update CHANGELOG and bump version