Adding overPotentialFoam and overRhoSimpleFoam and tutorials

tutorials/basic/overPotentialFoam/cylinder/Allclean

@@ -0,0 +1,11 @@
+#!/bin/sh
+cd ${0%/*} || exit 1    # run from this directory
+. $WM_PROJECT_DIR/bin/tools/CleanFunctions
+
+# Extrude mesh around cylinder
+(cd cylinderAndBackground && ./Allclean)
+
+# Add background mesh
+(cd cylinderMesh && foamCleanTutorials)
+
+# ----------------------------------------------------------------- end-of-file