Reorganize tests and add library folder

test/SimpleToken.test.js → test/examples/SimpleToken.test.js

-import decodeLogs from './helpers/decodeLogs';
-const SimpleToken = artifacts.require('examples/SimpleToken.sol');
+import decodeLogs from '../helpers/decodeLogs';
+const SimpleToken = artifacts.require('SimpleToken.sol');
 
 contract('SimpleToken', accounts => {
   let token;

test/ECRecovery.test.js → test/library/ECRecovery.test.js

-var ECRecoveryMock = artifacts.require('../contracts/mocks/ECRecoveryMock.sol');
-var ECRecoveryLib = artifacts.require('../contracts/ECRecovery.sol');
+var ECRecoveryMock = artifacts.require('ECRecoveryMock.sol');
+var ECRecoveryLib = artifacts.require('ECRecovery.sol');
 
-var hashMessage = require('./helpers/hashMessage.js');
+var hashMessage = require('../helpers/hashMessage.js');
 
 contract('ECRecovery', function (accounts) {
   let ecrecovery;

test/Math.test.js → test/library/Math.test.js

-var MathMock = artifacts.require('./mocks/MathMock.sol');
+var MathMock = artifacts.require('../mocks/MathMock.sol');
 
 contract('Math', function (accounts) {
   let math;

test/MerkleProof.test.js → test/library/MerkleProof.test.js

 
-import MerkleTree from './helpers/merkleTree.js';
+import MerkleTree from '../helpers/merkleTree.js';
 import { sha3, bufferToHex } from 'ethereumjs-util';
 
-var MerkleProof = artifacts.require('./MerkleProof.sol');
+var MerkleProof = artifacts.require('MerkleProof.sol');
 
 contract('MerkleProof', function (accounts) {
   let merkleProof;

test/token/DetailedERC20.test.js → test/token/erc/DetailedERC20.test.js

@@ -5,7 +5,7 @@ require('chai')
   .use(require('chai-bignumber')(BigNumber))
   .should();
 
-const DetailedERC20Mock = artifacts.require('mocks/DetailedERC20Mock.sol');
+const DetailedERC20Mock = artifacts.require('DetailedERC20Mock.sol');
 
 contract('DetailedERC20', accounts => {
   let detailedERC20 = null;

test/ERC827Token.js → test/token/erc/ERC827Token.js

 
-import EVMRevert from './helpers/EVMRevert';
-var Message = artifacts.require('./mock/MessageHelper.sol');
-var ERC827TokenMock = artifacts.require('./mock/ERC827TokenMock.sol');
+import EVMRevert from '../../helpers/EVMRevert';
+var Message = artifacts.require('MessageHelper.sol');
+var ERC827TokenMock = artifacts.require('ERC827TokenMock.sol');
 
 var BigNumber = web3.BigNumber;
 var _ = require('lodash');

test/token/SafeERC20.test.js → test/token/erc/SafeERC20.test.js

-import EVMThrow from '../helpers/EVMThrow';
+import EVMThrow from '../../helpers/EVMThrow';
 
 require('chai')
   .use(require('chai-as-promised'))
   .should();
 
-const SafeERC20Helper = artifacts.require('mocks/SafeERC20Helper.sol');
+const SafeERC20Helper = artifacts.require('SafeERC20Helper.sol');
 
 contract('SafeERC20', function () {
   beforeEach(async function () {