feat: Add support for template literals

[yokljo]

I added support for template literals. Here's the working test case:

it('should support template literals', () => {
  const code = `
    let a = \`world\`;
    let b = 1234;
    const result = \`hello \${a}\${a}, \\u{55} \${b * 2}! \${'test'}\`;
  `;

  const jinter = new Jinter();
  jinter.evaluate(code)

  expect(jinter.scope.get('result')).toBe('hello worldworld, U 2468! test');
});

[LuanRT]

Thanks!