I discovered a new `eval` library that reads strings of source and turns it...

I discovered a new `eval` library that reads strings of #python source and turns it into in-memory data.

## Serialization and deserialization times for 1000 dumps/loads
Oneway repr 0.11 seconds
Pickle: **0.07** seconds
JSON: 0.25 seconds
**asteval (repr + Interpreter()): 3.05 seconds**
HBN (repr + ast_eval, no validation): 2.60 seconds
HBN (repr + ast_eval + validation): 4.57 seconds
HBN (repr + eval): 2.14 seconds
HBN (repr + exec): 1.86 seconds
HBN (repr + by import): **0.96** seconds