ERC-725 General data key/value store and execution

DraftERCcreated 2017-10-021 later proposal build on itrequires ERC-165, ERC-173

An interface for a smart contract based account with attachable data key/value store

Authors: Fabian Vogelsteller (@frozeman), Tyler Yasaka (@tyleryasaka)

Functions this standard introduces (6)

`0x44c028fe`	`execute(uint256,address,uint256,bytes)`
`0x31858452`	`executeBatch(uint256[],address[],uint256[],bytes[])`
`0x54f6127f`	`getData(bytes32)`
`0xdedff9c6`	`getDataBatch(bytes32[])`
`0x7f23690c`	`setData(bytes32,bytes)`
`0x97902421`	`setDataBatch(bytes32[],bytes[])`

0x6c31b526 executeBatch(uint256[],address[],uint256[],bytes) IERC725X

Interfaces the spec defines alongside the core one, which an implementation may or may not carry.

`0x44c028fe`	`execute(uint256,address,uint256,bytes)`
`0x6c31b526`	`executeBatch(uint256[],address[],uint256[],bytes)`

Topic0 is the keccak256 hash of the signature, which is what a log filter matches on.

`0x4810874456b8e6487bd861375cf6abd8e1c8bb5858c8ce36a86a04dabfac199e`	`Executed(uint256,address,uint256,bytes4)`
`0xa1fb700aaee2ae4a2ff6f91ce7eba292f89c2f5488b8ec4c5c5c8150692595c3`	`ContractCreated(uint256,address,uint256,bytes32)`
`0xece574603820d07bc9b91f2a932baadf4628aabcb8afba49776529c14a6104b2`	`DataChanged(bytes32,bytes)`

Proposals this one names in its requires field.

Later proposals that name this one in their requires field.