Add a new set of templates

[filippsen]

Summary

Add a new set of templates.

Motivation

More templates to serve as base references and educational purposes.

[filippsen]

Consider new categories

• Ethereum.org [1] -- Check all balances -- Greeter -- Token -- Crowdsale -- DAO
• Solidity by example [2] -- Voting -- Open auction -- Blind auction -- Purchase -- Payment channel
• Token -- Standard (ERC-20) -- Non-Fungible Standard (ERC-721)
• Generic -- SafeMath -- Name Service (ENS)

[1] https://www.ethereum.org/cli [2] https://solidity.readthedocs.io/

[javier-tarazaga]

@filippsen Awesome initiative. We will need to figure out how to do a simplified version of the front-end for all those examples

[filippsen]

Additional template/example suggestions:

• Ethereum conversion helper tool (mentioned in #125)
• A message encoding/decoding tool using the in-browser wallet (mentioned in #126)