Add support for UnixWare in itclWidgets.
Don't let itclWidgets 4.0.0 depend on Itcl 4.0.1 only, it should work with Itcl 4.0.0 too.
In pkgIndex.tcl, check for Tcl8.6/Tk8.6/Itcl4.0 before trying to load itclWidgets shared library.