export pltcl target so that installed examples/tcl/standard_examples.in can be configured with the location of pltcl.
export pltcl target so that installed examples/tcl/standard_examples.in
can be configured with the location of pltcl.

svn path=/trunk/; revision=11121

FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot