consistency update

- OSspecific: chmod() -> chMod(), even although it's not used anywhere

- ListOps get subset() and inplaceSubset() templated on BoolListType

- added UList<bool>::operator[](..) const specialization.
  Returns false (actually pTraits<bool>::zero) for out-of-range elements.
  This lets us use List<bool> with lazy evaluation and no noticeable
  change in performance.

- use rcIndex() and fcIndex() wherever possible.
  Could check if branching or modulus is faster for fcIndex().

- UList and FixedList get 'const T* cdata() const' and 'T* data()' members.
  Similar to the STL front() and std::string::data() methods, they return a
  pointer to the first element without needing to write '&myList[0]', recast
  begin() or violate const-ness.

src/OpenFOAM/containers/HashTables/HashTable/HashTable.C

@@ -226,7 +226,7 @@ bool Foam::HashTable<T, Key, Hash>::set
     const bool protect
 )
 {
-    if (tableSize_ == 0)
+    if (!tableSize_)
     {
         resize(2);
     }
@@ -556,7 +556,7 @@ void Foam::HashTable<T, Key, Hash>::operator=
     }
 
     // could be zero-sized from a previous transfer()
-    if (tableSize_ == 0)
+    if (!tableSize_)
     {
         resize(rhs.tableSize_);
     }