ENH: avoid readScalar, readLabel etc from dictionary (#762, #1033)

- use the dictionary 'get' methods instead of readScalar for
  additional checking

     Unchecked:  readScalar(dict.lookup("key"));
     Checked:    dict.get<scalar>("key");

- In templated classes that also inherit from a dictionary, an additional
  'template' keyword will be required. Eg,

     this->coeffsDict().template get<scalar>("key");

  For this common use case, the predefined getXXX shortcuts may be
  useful. Eg,

     this->coeffsDict().getScalar("key");

src/OpenFOAM/interpolations/interpolationTable/tableReaders/csv/csvTableReader.C

@@ -33,10 +33,10 @@ template<class Type>
 Foam::csvTableReader<Type>::csvTableReader(const dictionary& dict)
 :
     tableReader<Type>(dict),
-    headerLine_(readBool(dict.lookup("hasHeaderLine"))),
-    timeColumn_(readLabel(dict.lookup("timeColumn"))),
+    headerLine_(dict.get<bool>("hasHeaderLine")),
+    timeColumn_(dict.get<label>("timeColumn")),
     componentColumns_(dict.lookup("valueColumns")),
-    separator_(dict.lookupOrDefault<string>("separator", string(","))[0])
+    separator_(dict.lookupOrDefault<string>("separator", ",")[0])
 {
     if (componentColumns_.size() != pTraits<Type>::nComponents)
     {