optimizer for boolean

[Fitznik]

The structure of the BooleanWrapper is created. Added storage. The tests are correct. Optimization is successful.

[shamatar]

Please move this work to VM directly and do at least the following changes:

• remove a global state. Currently if during execution of the same program in two different circuits the same variable will be boolean then it would mix them
• do not implement equality and such things for Boolean. Use wrapper type for it. And we already have such equality in VM
• do not use String for operation type. Use enum instead
• add function for long-ors and long-ands, when there are chains like a | b | c | d, and we have a | b already memoized