Fixed __builtin_clz and __builtin_ctz.
Added foundaton::is_trivially_constructable.
foundation::Pair now requires default constructors for key/value.
Fixed foundation::String corner cases (operator= with a null string).
Containers default initialize and use copy constructors for new elements.
Added optimizied_construct.
Added recursive ability to Directory::destroy.
Fixed premature typecast during epoch conversion in Directory::scan.