Changed the general reference to the Wiki to the specific page regarding Cygwin.
Changed the general reference to the Wiki to the specific page regarding Cygwin.

svn path=/trunk/; revision=12515

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