Fix FIXME, rearrange and rename instr blocks.

Stop relying on a property that isn't guaranteed to hold (the ordering of BasicBlocks within a Function) and make sure all blocks are in a sensible order with programmer-meaningful names.
Build 'strawman' with debug info.
Keep all .ll files around for diffing.
Actually, DES_set_key ought to return 0.
Move operator==() into separate file.
Add operator==(NowEvent x 2).
Store transitions in expr-based equivalence sets.

This is the next step on the road to actually using 'struct tesla_transitions' properly.