dream: unset PYTHONPATH to be able to find modules in virtualenv

software/dream/software.cfg

@@ -76,6 +76,7 @@ update_cmd = ${:install_cmd}
 recipe = collective.recipe.template
 output = ${buildout:directory}/environment.sh
 input = inline:
+  unset PYTHONPATH
   export PATH="${r-language:location}/bin:$PATH"
   export LD_LIBRARY_PATH="`${r-language:location}/bin/R RHOME`/lib:$LD_LIBRARY_PATH"
   export LD_PRELOAD=${gcc-fortran:location}/lib64/libgfortran.so.3