Replace all asserts with chai.should (#1183)

* Moving towards chai.should.

* Fixed failing tests.

* Fixed linter errors.

* Revert package-lock.json changes.

* Fixed failing tests.

* s/eq/equal

* Addressed review comment

test/library/Math.test.js

@@ -1,5 +1,11 @@
 const MathMock = artifacts.require('MathMock');
 
+const BigNumber = web3.BigNumber;
+
+require('chai')
+  .use(require('chai-bignumber')(BigNumber))
+  .should();
+
 contract('Math', function () {
   const min = 1234;
   const max = 5678;
@@ -11,24 +17,24 @@ contract('Math', function () {
   describe('max', function () {
     it('is correctly detected in first argument position', async function () {
       const result = await this.math.max(max, min);
-      assert.equal(result, max);
+      result.should.be.bignumber.equal(max);
     });
 
     it('is correctly detected in second argument position', async function () {
       const result = await this.math.max(min, max);
-      assert.equal(result, max);
+      result.should.be.bignumber.equal(max);
     });
   });
 
   describe('min', function () {
     it('is correctly detected in first argument position', async function () {
       const result = await this.math.min(min, max);
-      assert.equal(result, min);
+      result.should.be.bignumber.equal(min);
     });
 
     it('is correctly detected in second argument position', async function () {
       const result = await this.math.min(max, min);
-      assert.equal(result, min);
+      result.should.be.bignumber.equal(min);
     });
   });
 });