ENH: unify use of dictionary method names

- previously introduced `getOrDefault` as a dictionary _get_ method,
  now complete the transition and use it everywhere instead of
  `lookupOrDefault`. This avoids mixed usage of the two methods that
  are identical in behaviour, makes for shorter names, and promotes
  the distinction between "lookup" access (ie, return a token stream,
  locate and return an entry) and "get" access (ie, the above with
  conversion to concrete types such as scalar, label etc).

etc/codeTemplates/BC/BC.C

@@ -79,7 +79,7 @@ CONSTRUCT
     data_(dict.get<TYPE>("data")),
     fieldData_("fieldData", dict, p.size()),
     timeVsData_(Function1<TYPE>::New("timeVsData", dict)),
-    wordData_(dict.lookupOrDefault<word>("wordName", "wordDefault")),
+    wordData_(dict.getOrDefault<word>("wordName", "wordDefault")),
     labelData_(-1),
     boolData_(false)
 {