Write the OmiseGO eWallet Name Service Smart Contract

[T-Dnzt]

From our current understanding, ENS is not enough for our needs. We'll need to write a very simple contract for eWallet to register themselves with their public key and the current domain name of their eWallet.

We need the following functions:

• Get all
• Get one
• Register (or update)
• Delete (or set to null)

[unnawut]

Notes from previous discussions:

• This OENS is a reverse DNS where it maps a blockchain address -> a URI where the eWallet server resides (e.g. 0xABCD... -> https://www.example.com:4000/).
• This is used when two independent eWallet providers want to talk to each other, while knowing only the blockchain address (which should be very infrequently changed).
• The blockchain address is the master wallet's primary wallet address.
• This would be one universal OENS contract that acts as the registry for all eWallets in the world.