Add a 'clean' option to paraview/install.sh

paraview/install.sh

@@ -91,6 +91,15 @@ envtpl  --keep-template -o $MODULE_PATH module.tmpl
 if [[ $1 == "module" ]]
 then
   install_module
+elif [[ $1 == "clean" ]]
+then
+  if [[ -d $BUILD_DIR ]]
+  then
+    rm -rf $BUILD_DIR
+  else
+    echo "$BUILD_DIR does not exist"
+    exit 1
+  fi
 else
   install_lib
   install_module