ENH: simplify method names for reading argList options and arguments

- use succincter method names that more closely resemble dictionary
  and HashTable method names. This improves method name consistency
  between classes and also requires less typing effort:

    args.found(optName)        vs.  args.optionFound(optName)
    args.readIfPresent(..)     vs.  args.optionReadIfPresent(..)
    ...
    args.opt<scalar>(optName)  vs.  args.optionRead<scalar>(optName)
    args.read<scalar>(index)   vs.  args.argRead<scalar>(index)

- the older method names forms have been retained for code compatibility,
  but are now deprecated

applications/utilities/mesh/generation/extrude/extrudeMesh/extrudeMesh.C

@@ -268,7 +268,7 @@ int main(int argc, char *argv[])
     // Get optional regionName
     word regionName;
     word regionDir;
-    if (args.optionReadIfPresent("region", regionName))
+    if (args.readIfPresent("region", regionName))
     {
         regionDir = regionName;
         Info<< "Create mesh " << regionName << " for time = "

applications/utilities/mesh/generation/extrude/extrudeToRegionMesh/extrudeToRegionMesh.C

@@ -1473,8 +1473,6 @@ void extrudeGeometricProperties
 }
 
 
-
-
 int main(int argc, char *argv[])
 {
     argList::addNote("Create region mesh by extruding a faceZone or faceSet");
@@ -1501,8 +1499,7 @@ int main(int argc, char *argv[])
 
 
     const word oldInstance = mesh.pointsInstance();
-    bool overwrite = args.optionFound("overwrite");
-
+    const bool overwrite = args.found("overwrite");
 
     const word dictName("extrudeToRegionMeshDict");
 
@@ -1510,11 +1507,9 @@ int main(int argc, char *argv[])
 
     IOdictionary dict(dictIO);
 
-
     // Point generator
     autoPtr<extrudeModel> model(extrudeModel::New(dict));
 
-
     // Region
     const word shellRegionName(dict.lookup("region"));
 
@@ -1522,7 +1517,7 @@ int main(int argc, char *argv[])
     wordList zoneNames;
     wordList zoneShadowNames;
 
-    bool hasZones = dict.found("faceZones");
+    const bool hasZones = dict.found("faceZones");
     if (hasZones)
     {
         dict.lookup("faceZones") >> zoneNames;