support to_string on c++ base types

alib2std/src/deque

alib2std/src/extensions/deque.hpp

alib2std/src/extensions/forward_list.hpp

alib2std/src/extensions/forward_tree.hpp

alib2std/src/extensions/linear_set.hpp

alib2std/src/extensions/list.hpp

alib2std/src/extensions/map.hpp

alib2std/src/extensions/pair.hpp

alib2std/src/extensions/set.hpp

alib2std/src/extensions/tree.hpp

alib2std/src/extensions/tuple.hpp

alib2std/src/extensions/unordered_map.hpp

alib2std/src/extensions/variant.hpp

alib2std/src/extensions/vector.hpp

alib2std/src/forward_list

alib2std/src/forward_tree

alib2std/src/istream

alib2std/src/linear_set

alib2std/src/list

alib2std/src/map