fix stack item deserialization for Boolean VM type

[ixje]

What current issue(s) does this address, or what feature is it adding?
audit of testnet block 2591458 showed a deviation in storage value due to wrong a deserialization of a Boolean VM type. This was caused by the Boolean type receiving an integer as value as opposed to a bool type. This resulted in deserializing the value 44 as opposed to True, leading to a 0x01 0x2c instead of 0x01 0x01.

How did you solve this problem?
convert int to bool for stack item deserialization

How did you make sure your solution works?
audit of block passes

Are there any special changes in the code that we should be aware of?

Please check the following, if applicable:

• Did you add any tests?
• Did you run make lint?
• Did you run make test?
• Are you making a PR to a feature branch or development rather than master?
• Did you add an entry to CHANGELOG.rst? (if not, please do)

[coveralls]

Coverage remained the same at 85.28% when pulling 2af702e on ixje:fix-boolean-type into a350388 on CityOfZion:development.