Desuckified header inclusions, and added test for unistd.h before including it.
Desuckified header inclusions, and added test for unistd.h before
including it.

svn path=/trunk/; revision=1178

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