ERC-900 Simple Staking Interface

StagnantERCcreated 2018-02-22

Authors: Dean Eigenmann, Jorge Izquierdo

ERC-165 interface ids

Computed here as the XOR of the selectors each interface defines.

Staking 0x89e03aac

`0x233b7451`	`lastStakedFor(address)`	view
`0x0e89439b`	`stake(uint256,bytes)`
`0x0ef96356`	`stakeFor(address,uint256,bytes)`
`0x7033e4a6`	`supportsHistory()`	pure
`0xfc0c546a`	`token()`	view
`0x817b1cd2`	`totalStaked()`	view
`0xc9c53232`	`totalStakedAt(uint256)`	view
`0x4b341aed`	`totalStakedFor(address)`	view
`0xede38421`	`totalStakedForAt(address,uint256)`	view
`0xc8fd6ed0`	`unstake(uint256,bytes)`

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

`0xc65e53b88159e7d2c0fc12a0600072e28ae53ff73b4c1715369c30f160935142`	`Staked(address,uint256,uint256,bytes)`
`0xaf01bfc8475df280aca00b578c4a948e6d95700f0db8c13365240f7f973c8754`	`Unstaked(address,uint256,uint256,bytes)`