Log Message:
Changes 1.11:
* Fix assignment to lvalue accessors that point at an uninitialized hash
  element.

Changes 1.10:
* We don't occasionally crash during END any more. Instead, we rely on the OS
  to reap a bit of memory after perl was shut down anyway.
* Tiny refactoring for smaller object size.

Changes 1.09:
* Fix: Predicates return value, not bool
* TODO test for perl-crashing bug (in perl) that can happen
  on (arcane) XSUB aliasing on perls < 5.8.9
  We're open for work-around patches.