ENH: make sourceInfo sub-dictionary optional for topoSet (#1060)

- helps reduce clutter in the topoSetDict files.

  Caveats when using this.

  The older specification styles using "name" will conflict with the
  set name. Eg,

    {
        name    f0
        type    faceSet;
        action  add;
        source  patchToFace;
        sourceInfo
        {
            name   inlet;
        }
    }

    would flattened to the following
    {
        name    f0
        type    faceSet;
        action  add;
        source  patchToFace;
        name   inlet;
    }
    which overwrites the "name" used for the faceSet.

    The solution is to use the updated syntax:

    {
        name    f0
        type    faceSet;
        action  add;
        source  patchToFace;
        patch   inlet;
    }

tutorials/multiphase/interIsoFoam/discInReversedVortexFlow/system/topoSetDict

@@ -22,15 +22,12 @@ actions
         type    cellSet;
         action  new;
         source  boxToCell;
-        sourceInfo
-        {
-            boxes
-            (
-                (.1 -1e10 0.08) (.9 1e10 0.2)
-                (.75 -1e10 0.2) (.92 1e10 0.9)
-                (.1 -1e10 0.2) (.25 1e10 0.7)
-            );
-        }
+        boxes
+        (
+            (0.1 -1e10 0.08) (0.9 1e10 0.2)
+            (0.75 -1e10 0.2) (0.92 1e10 0.9)
+            (0.1 -1e10 0.2) (0.25 1e10 0.7)
+        );
     }
 );
 

tutorials/multiphase/interIsoFoam/discInReversedVortexFlow/system/topoSetDict2

@@ -22,13 +22,10 @@ actions
         type    cellSet;
         action  new;
         source  boxToCell;
-        sourceInfo
-        {
-            boxes
-            (
-                (.4 -1e10 0.09) (.7 1e10 0.15)
-            );
-        }
+        boxes
+        (
+            (0.4 -1e10 0.09) (0.7 1e10 0.15)
+        );
     }
 );