END -> ::end

Reverted Amorilia's end -> END substitutions (seems that Amorilia has
forgot to revert all affected files).
Include paths for niflib fixed

Niflib include path was pointing to incorrect folder, not the one
fetched as submodule
Project revived

Last commits from theru killed NifPlugins* project file, don't think
that was intended.
Still have to fix props files to conform with Environment variable names
for 3ds max and its SDK.