New browsers options

[mmarkelov]

close #539

It will be able to specify browsers in this way:

// jest-playwright.config.js
{
  ...,
  browsers: ['firefox', {
    displayName: 'edge',
    name: 'chromium',
    launchOptions: {
      headless: false,
      executablePath: '/Applications/Microsoft Edge.app/Contents/MacOS/Microsoft Edge'
    }
  }],
}

[coveralls]

Pull Request Test Coverage Report for Build 504112739

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 95.906%

---

Totals
Change from base Build 502061777:	0.0%
Covered Lines:	105
Relevant Lines:	107

---

💛 - Coveralls

[PaulRosset]

Thanks!