ENH: region-wise decomposition specification for decomposeParDict

Within decomposeParDict, it is now possible to specify a different
  decomposition method, methods coefficients or number of subdomains
  for each region individually.

  The top-level numberOfSubdomains remains mandatory, since this
  specifies the number of domains for the entire simulation.
  The individual regions may use the same number or fewer domains.

  Any optional method coefficients can be specified in a general
  "coeffs" entry or a method-specific one, eg "metisCoeffs".

  For multiLevel, only the method-specific "multiLevelCoeffs" dictionary
  is used, and is also mandatory.

----

ENH: shortcut specification for multiLevel.

  In addition to the longer dictionary form, it is also possible to
  use a shorter notation for multiLevel decomposition when the same
  decomposition method applies to each level.

src/parallel/decompose/decompositionMethods/geomDecomp/geomDecomp.H

@@ -25,7 +25,14 @@ Class
     Foam::geomDecomp
 
 Description
-    Geometrical domain decomposition
+    Base for geometrical domain decomposition methods
+
+    Base coefficients:
+    \table
+        Property  | Description                 | Required | Default
+        n         | (nx ny nz)                  | yes
+        delta     | delta for rotation matrix   | no | 0.001
+    \endtable
 
 SourceFiles
     geomDecomp.C
@@ -42,36 +49,56 @@ namespace Foam
 {
 
 /*---------------------------------------------------------------------------*\
-                           Class geomDecomp Declaration
+                         Class geomDecomp Declaration
 \*---------------------------------------------------------------------------*/
 
 class geomDecomp
 :
     public decompositionMethod
 {
+    // Private Member Functions
+
+        //- Read input values and initialize the rotDelta_
+        void readCoeffs();
+
 
 protected:
 
     // Protected data
 
-        const dictionary& geomDecomDict_;
+        //- Coefficients for all derived methods
+        const dictionary& coeffsDict_;
 
         Vector<label> n_;
+
+        //- Default = 0.001
         scalar delta_;
+
         tensor rotDelta_;
 
 public:
 
     // Constructors
 
-        //- Construct given the decomposition dictionary
-        //  and the derived type name
+        //- Construct for derived type name and decomposition dictionary
         geomDecomp
         (
-            const dictionary& decompositionDict,
-            const word& derivedType
+            const word& derivedType,
+            const dictionary& decompDict,
+            int select = selectionType::DEFAULT
         );
 
+        //- Construct for derived type name, decomposition dictionary
+        //- and region name
+        geomDecomp
+        (
+            const word& derivedType,
+            const dictionary& decompDict,
+            const word& regionName,
+            int select = selectionType::DEFAULT
+        );
+
+
         //- Return for every coordinate the wanted processor number.
         virtual labelList decompose
         (