NULL _all_ unset values when resizing during push

This prevents reinit from crashing.
Always calculate the new top after pushing

This way we don't end up in no mans' land when calling teh deinit
callback.
Fix transaction deinitialization

We shall not deinitialize uninitialized parts of an array!!!11eleven
Merge pull request #336 from neithernut/fix-action_processor

Fix action processor