added options (but not yet implementation) for providing a callback after all operations are complete and for overriding the default ajax type. modernized thesaurus ajax call
ok now all those things i said
cached thesaurus to prevent multiple ajax calls, removed splicing of thesaurus so that future 'reset' calls to thesaurus are unnecessary. i decided to do this because after all, this is a prototyping library, so i feel that speed and performance is much more important than ensuring the integrity of the randomness of sentences. also implemented callback after all operations are complete