Remove the "thingpedia_as_context" option, and the different ThingTalk
grammars. They were unused, and also unlikely to be helpful, after
several experiments.
torchtext never really took off as the official PyTorch library
for text, and we've been using an embedded fork for a while.
Acknowledge that, merge the code, and stop treating it like
a separate project.
Cove is an obsolete form of pretraining, of dubious utility. It
depends on an obsolete, unmaintained, library, and it causes
hacks in the code. Clean up.
Giovanni Campagna