Merge note: currently cannot compile due to `quasiBoolean` (#63). This will be solved by https://github.com/status-im/nimbus/pull/65
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* Implemented most of the stubbed out state handling instructions
The code compiles, but still fails at the moment due to incorrect
initialization of the VM. Don't merge yet. More commits will be
pushed in the coming days.
* Fixed crash
* trie put and del are void now
* getBlockTransactionData and getReceipts
* Working code for extcodesize0.json
* fix origin.json
* fix calldatasize1
* fix calldataloadSizeTooHighPartial
* fix calldataloadSizeTooHigh
* more efficient PushX implementation
* fix and, or, xor
* `usedBytes` was not named appropriately. it indicates the last
populated position in the data (the last valid index) for slicing
purposes (i.e. the position is passed to `toOpenArray`)
* Fixed the `==` operator for DBKeys
* Use one-byte key for the 'canonical head hash'
Yuriy Glukhov
cheatfate
zah