This patch adds a new configure option --with-pltcl-unknown which
enables pltcl unknown support.
Also it adds substituting of tclsh with tclsh that was by configure in
pltcl_*mod scripts. For example, On freebsd, tclsh can be called
tclsh8.2 or
tclsh8.3 depending on installed version of Tcl.
After patching files
src/pl/tcl/modules/pltcl_listmod
src/pl/tcl/modules/pltcl_loadmod
src/pl/tcl/modules/pltcl_delmod
must be renamed(copied,repocopied) to
src/pl/tcl/modules/pltcl_listmod.in
src/pl/tcl/modules/pltcl_loadmod.in
src/pl/tcl/modules/pltcl_delmod.in