Added option to pass juiceResources with render and renderAll

[maabiddevra]

• Option to override juice global settings https://github.com/Automattic/juice#juicecodeblockss
• If you need pass juiceResources in render function, with this option you don't need create Email instance every time

  const Email = require('email-templates');
  const email = new Email();
  email
  .render({
  path: 'mars/html',
  juiceResources: {
    preserveImportant: true,
    webResources: {
      // view folder path, it will get css from `mars/style.css`
      relativeTo: path.resolve('mars')
    }
  }
  }, {
  name: 'Elon'
  })
  .then(console.log)
  .catch(console.error);

The example above will be useful when you have a structure like this, this will be useful when you have a separate CSS file for every template

.
├── app.js
└── emails
    └── mars
        ├── html.pug
        ├── text.pug
        ├── subject.pug
        └── style.css

[maabiddevra]

@niftylettuce Can you review this PR

[niftylettuce]

v7.1.1 released to npm, thank you https://github.com/forwardemail/email-templates/releases/tag/v7.1.1

[maabiddevra]

Thank you for considering.