ENH: adjustments for Function1/PatchFunction1

- additional debug information

- improve support for dictionary specification of constant, polynomial
  and table entries. These previously only worked properly for
  primitiveEntry, which causes confusion.

- extend table Function1 to include TableFile functionality.
  Simplifies switching and modifying content.

tutorials/incompressible/pimpleFoam/RAS/TJunctionFan/0.orig/p

@@ -25,11 +25,10 @@ boundaryField
     {
         type            fanPressure;
         direction       in;
-        fanCurve        tableFile;
-        fanCurveCoeffs
+        fanCurve
         {
-            file        "<constant>/FluxVsdP.dat";
-            // readerType  openFoam;   // Default
+            type table;
+            file "<constant>/FluxVsdP.dat";
             // outOfBounds clamp;      // Default
         }
         //nonDimensional  true;