Lists get first() and last() member functions

- this builds on Mattijs' commit 968f0bbd57 but with a first()
  as well.

- Added both to FixedList, IndirectList, UIndirectList and *PtrList and
  since they can certainly be useful there. Did not add to BiIndirectList,
  since I'm not sure what it should mean there. Did not add to PackedList,
  since it's not clear how useful they'd be yet in these contexts (and I'm
  not sure how it would interact with the iterator proxy implementation).

- Note: STL defines front() and back() for these methods.

src/OpenFOAM/containers/HashTables/HashTable/HashTable.H

@@ -287,7 +287,7 @@ public:
             void shrink();
 
             //- Transfer the contents of the argument table into this table
-            //  and annull the argument table.
+            //  and annul the argument table.
             void transfer(HashTable<T, Key, Hash>&);
 
             //- Transfer contents to the Xfer container
@@ -463,7 +463,7 @@ public:
                 inline iterator operator++(int);
         };
 
-        //- iterator set to the begining of the HashTable
+        //- iterator set to the beginning of the HashTable
         inline iterator begin();