Removed from VirtualLeaf and libplugin project files their explicit perl invocation to regerenerate parameter files.

--
user: Michael Guravage <michael.guravage@cwi.nl>
branch 'default'

changed src/ChangeLog
changed src/Makefile
changed src/VirtualLeaf.pro
changed src/build_models/Makefile
changed src/libplugin.pro