The 8.6 core zlib cannot be used for the vfs::zstreamed mode that

The 8.6 core zlib cannot be used for the vfs::zstreamed mode that
is used with mk4vfs. This commit disabled zstreamed for 8.6 so we
will never call this tclvfs function for 8.6 tclkits.
The tclvfs pkgIndex code has been moved from files/ into setupvfs.tcl
to make it easier to handle new versions of tclvfs.
Makefile.vc gets some post-build sanity checking to ensure we do not
produce useless tclkits.

git-svn-id: svn://svn.equi4.com/kitgen/trunk@4468 9e558909-932a-0410-a563-af77432da1eb