Changed to 5.7.4 release. Added a note about CVS to SVN conversion.
Changed to 5.7.4 release. Added a note about CVS to SVN conversion.

svn path=/trunk/; revision=7658

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