foamCleanPolyMesh: No need to warn about missing 'polyMesh' directories

bin/foamCleanPolyMesh

@@ -3,7 +3,7 @@
 # =========                 |
 # \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
 #  \\    /   O peration     |
-#   \\  /    A nd           | Copyright (C) 2011-2015 OpenFOAM Foundation
+#   \\  /    A nd           | Copyright (C) 2011-2016 OpenFOAM Foundation
 #    \\/     M anipulation  |
 #-------------------------------------------------------------------------------
 # License
@@ -50,7 +50,7 @@ USAGE
 
 unset caseDir regionName
 
-# parse a single option
+# Parse a single option
 while [ "$#" -gt 0 ]
 do
     case "$1" in
@@ -81,12 +81,12 @@ else
     meshDir=polyMesh
 fi
 
-# if -case was specified: insist upon 'constant/polyMesh'
+# If -case was specified: insist upon 'constant/polyMesh'
 if [ -n "$caseDir" ]
 then
     if [ -d constant/$meshDir ]
     then
-        # use constant/polyMesh
+        # Use constant/polyMesh
         meshDir=constant/$meshDir
     else
        echo "Error: no 'constant/$meshDir' in $caseDir" 1>&2
@@ -95,27 +95,22 @@ then
 else
     if [ -d constant/$meshDir ]
     then
-        # use constant/polyMesh
+        # Use constant/polyMesh
         meshDir=constant/$meshDir
     elif [ -d $meshDir ]
     then
-        # likely already in constant/ - do not adjust anything
+        # Likely already in constant/ - do not adjust anything
         :
     elif [ "${PWD##*/}" = polyMesh -a -z "$regionName" ]
     then
-        # apparently already within polyMesh/
+        # Apparently already within polyMesh/
         meshDir=.
-    else
-        echo "Error: no appropriate 'polyMesh/' directory found" 1>&2
-        exit 1
     fi
 fi
 
 
-#
-# remove files (mesh itself, modifiers, snappyHexMesh ones) and subdirectories
+# Remove files (mesh itself, modifiers, snappyHexMesh ones) and subdirectories
 # also remove .gz versions of the same files
-#
 echo "Cleaning ${caseDir:-.}/$meshDir" 1>&2
 
 for i in \