Fails to work for the 0x v2 `Exchange` contract

```
➜ rattle git:(master) ✗ python3 rattle-cli.py --input ../code.bytecode -O
Traceback (most recent call last):
File "rattle-cli.py", line 203, in
main()
File "rattle-cli.py", line 48, in main
ssa = rattle.Recover(args.input.read(), edges=edges, optimize=args.optimize)
File "/Users/___/Projects/Ethereum/rattle/rattle/recover.py", line 712, in __init__
self.internal = InternalRecover(filedata, edges, optimize)
File "/Users/___/Projects/Ethereum/rattle/rattle/recover.py", line 41, in __init__
self.recover(dispatch)
File "/Users/___/Projects/Ethereum/rattle/rattle/recover.py", line 75, in recover
self.identify_blocks(function)
File "/Users/___/Projects/Ethereum/rattle/rattle/recover.py", line 185, in identify_blocks
block.set_fallthrough_target(terminator.offset + terminator.insn.size)
File "/Users/___/Projects/Ethereum/rattle/rattle/ssa.py", line 478, in set_fallthrough_target
target_block : SSABasicBlock = self.function.blockmap[other]
KeyError: 22707
```

`code.bytecode` created with `cat code.bin | xxd -r -ps > code.bytecode` whereas `code.bin` is https://gist.github.com/reverendus/9151b4d7b154b63fd55ae663fa6465a4. I'm on the recent `master` i.e. `2ec580f6963ee876b90326576bc328cca0d03c79`.