functionObjects: Moved into the functionObjects namespace and rationalized and simplified failable construction

Rather than requiring each functionObject to handle failed construction
internally (using the active_ flag) the static member function "viable"
is provided which returns true if construction of the functionObject is
likely to be successful.  Failed construction is then handled by the
wrapper-class which constructs the functionObject,
e.g. "OutputFilterFunctionObject".

src/postProcessing/functionObjects/utilities/Peclet/Peclet.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2013 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2013-2016 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -22,7 +22,7 @@ License
     along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
 
 Class
-    Foam::Peclet
+    Foam::functionObjects::Peclet
 
 Group
     grpUtilitiesFunctionObjects
@@ -56,6 +56,9 @@ class dictionary;
 class polyMesh;
 class mapPolyMesh;
 
+namespace functionObjects
+{
+
 /*---------------------------------------------------------------------------*\
                           Class Peclet Declaration
 \*---------------------------------------------------------------------------*/
@@ -70,9 +73,6 @@ class Peclet
         //- Reference to the database
         const objectRegistry& obr_;
 
-        //- On/off switch
-        bool active_;
-
         //- Name of flux field, default is "phi"
         word phiName_;
 
@@ -107,6 +107,16 @@ public:
             const bool loadFromFiles = false
         );
 
+        //- Return true if the construction of this functionObject is viable
+        //  i.e. the prerequisites for construction are available
+        static bool viable
+        (
+            const word& name,
+            const objectRegistry&,
+            const dictionary&,
+            const bool loadFromFiles = false
+        );
+
 
     //- Destructor
     virtual ~Peclet();
@@ -147,6 +157,7 @@ public:
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
+} // End namespace functionObjects
 } // End namespace Foam
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //