Fixed eslint error and integrated with prettier

[ZeroX-DG]

Description

This PR fixed eslint error when eslint is upgraded to v4 due to conflict with prettier. What this PR does is it integrated eslint with prettier so that the prettify process will have no conflict with the linting config. In addition, this PR also pretty the code to fix this PR: #3325

Issue fixed

• Bump eslint from 3.19.0 to 4.18.2 #3325

Type of changes

• ⚪ Bug fix (Change that fixed an issue)
• ⚪ Breaking change (Change that can cause existing functionality to change)
• 🔘 Improvement (Change that improves the code. Maybe performance or development improvement)
• ⚪ Feature (Change that adds new functionality)
• ⚪ Documentation change (Change that modifies documentation. Maybe typo fixes)

Checklist:

• 🔘 My code follows the project code style
• ⚪ I have written test for my code and it has been tested
• ⚪ All existing tests have been passed
• ⚪ I have attached a screenshot/video to visualize my change if possible

[ZeroX-DG]

@Rokt33r can you review this please?

[Rokt33r]

We should configure prettier too!

.prettierrc

{
  "singleQuote": true,
  "semi": false,
  "jsxSingleQuote": true
}

[ZeroX-DG]

@Rokt33r I added prettier config and run the prettier again to reduce the changes.