Changed PACKAGE_VERSION to PLPLOT_PACKAGE_VERSION, since the former is apparently used in autoconf 2.52 and our use isn't compatible.
Changed PACKAGE_VERSION to PLPLOT_PACKAGE_VERSION, since the former is
apparently used in autoconf 2.52 and our use isn't compatible.

svn path=/trunk/; revision=3520

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