Corrected error in install location and cleaned up logic so that README.python does not become executable.
Corrected error in install location and cleaned up logic so that README.python
does not become executable.

svn path=/trunk/; revision=2608

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