functionObjects: rewritten to all be derived from 'functionObject'

- Avoids the need for the 'OutputFilterFunctionObject' wrapper
  - Time-control for execution and writing is now provided by the
    'timeControlFunctionObject' which instantiates the processing
    'functionObject' and controls its operation.
  - Alternative time-control functionObjects can now be written and
    selected at run-time without the need to compile wrapped version of
    EVERY existing functionObject which would have been required in the
    old structure.
  - The separation of 'execute' and 'write' functions is now formalized in the
    'functionObject' base-class and all derived classes implement the
    two functions.
  - Unnecessary implementations of functions with appropriate defaults
    in the 'functionObject' base-class have been removed reducing
    clutter and simplifying implementation of new functionObjects.
  - The 'coded' 'functionObject' has also been updated, simplified and tested.
  - Further simplification is now possible by creating some general
    intermediate classes derived from 'functionObject'.

src/OpenFOAM/db/functionObjects/functionObjectList/functionObjectList.H

@@ -29,7 +29,8 @@ Description
     that is called for each object.
 
 See Also
-    Foam::functionObject and Foam::OutputFilterFunctionObject
+    Foam::functionObject
+    Foam::functionObjects::timeControl
 
 SourceFiles
     functionObjectList.C
@@ -158,6 +159,9 @@ public:
         //- Find the ID of a given function object by name
         label findObjectID(const word& name) const;
 
+        //- Read and set the function objects if their data have changed
+        bool read();
+
         //- Switch the function objects on
         void on();
 
@@ -184,9 +188,6 @@ public:
         //- Called at the end of Time::adjustDeltaT() if adjustTime is true
         bool adjustTimeStep();
 
-        //- Read and set the function objects if their data have changed
-        bool read();
-
         //- Update for changes of mesh
         void updateMesh(const mapPolyMesh& mpm);