Use the CMake variable plplottcltk_SOVERSION as the suffix for the Tcl/Tk library, so that the pkgIndex.tcl file is adjusted automatically.
Use the CMake variable plplottcltk_SOVERSION as the suffix for the Tcl/Tk library, so that the pkgIndex.tcl file is adjusted automatically.

svn path=/trunk/; revision=12941

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