Remove test_some_diff_psc target which tends to encourage bogus multiple-target use of parallel builds.
Remove test_some_diff_psc target which tends to encourage bogus
multiple-target use of parallel builds.

Rename important test_all_diff_psc target as test_diff_psc.


svn path=/trunk/; revision=10496

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