- equality operators <tt>==</tt> and <tt>!=</tt>.\r
Iterators are equal iff they point to the same cell of the same array node.
Note that for two iterators \p it1 and \p it2, the conditon <tt> it1 == it2 </tt>
- does not entail <tt> &(*it1) == &(*it2) </tt>: welcome to concurrent containers
+ does not entail <tt> &(*it1) == &(*it2) </tt>
- helper member function \p release() that clears internal hazard pointer.\r
After \p release() call the iterator points to \p nullptr but it still remain valid: further iterating is possible.
*/