Create babble.c

All of the functions pertaining to the babbling itself (i.e. producing first words, next words, sentences, paragraphs, etc. from the hash table).

* Currently there is a bug in which in htable_search to search for a given words entry, it causes a segfault. This has been located down to the strlen call in infrastructure.c, particularly the hash function. There is some sort of corruption with the words themselves causing this segfault. See infrastructure.c for more info.