Add ahtable load/save

I need to add tests for this (and obviously, extend load/save to the trie object), but I'm not sure how to get the tests going. Consider me a newb at autoconf, etc. Right now, I have a Makefile and a Makefile.am in the test/ directory, but no executables in there. What do I do to create check_ahtable from check_ahtable.c?
It makes the persistent format not very portable. If we copy the file from 64bit machine to 32bit machine, it fails.
It will be better to use fixed length stdints.
Also, the endian should be considered too...