tutorials: Remove the unnecessary "\"s on "cp", "rm" and "mv"

Resolves bug-report http://bugs.openfoam.org/view.php?id=2077

tutorials/multiphase/interPhaseChangeDyMFoam/propeller/Allclean

@@ -5,10 +5,10 @@ cd ${0%/*} || exit 1    # Run from this directory
 . $WM_PROJECT_DIR/bin/tools/CleanFunctions
 
 # remove surface
-\rm -f constant/triSurface/propellerTip.obj.gz > /dev/null 2>&1
+rm -f constant/triSurface/propellerTip.obj.gz > /dev/null 2>&1
 
 cleanCase
 
-\rm -rf 0 > /dev/null 2>&1
-\rm -rf constant/extendedFeatureEdgeMesh > /dev/null 2>&1
-\rm -f constant/triSurface/*.eMesh* > /dev/null 2>&1
+rm -rf 0 > /dev/null 2>&1
+rm -rf constant/extendedFeatureEdgeMesh > /dev/null 2>&1
+rm -f constant/triSurface/*.eMesh* > /dev/null 2>&1

tutorials/multiphase/interPhaseChangeDyMFoam/propeller/Allrun.pre

@@ -19,7 +19,7 @@ runApplication snappyHexMesh -overwrite
 runApplication renumberMesh -overwrite
 
 # force removal of fields generated by snappy
-\rm -rf 0
+rm -rf 0
 
 
 # - generate face/cell sets and zones