Still deadlocks in one case, due to spurious dependencies inside traversals.  See next commit.

realloc() has that horrible overloaded free semantics.

By faking them out to length 1, we might go oob.  Just fake the malloc.

Important change:  array_pop no longer checks if the array has elements; use array_pop_check in its place.

I have given my array module a makeover (see attached
array-0.1.tar.bz2 ).  Major changes are:

* All the macros have been renamed to flat array_* names.  Instead of
Array, AInit, AAppend, etc., it is now array, array_init,
array_append, etc..  This will obviously break any applications
already using the array module (if any); 'renames' is the list of sed
commands I used to make the name changes.
* array (by default) now uses talloc functions instead of regular
malloc/realloc/free.
* All of the array macros have tests now.