v0.5.5

• Feature: Simplify usage by supporting new default loop.
  (#134 by @clue)

  // old (still supported)
  $factory = new React\MySQL\Factory($loop);
  
  // new (using default loop)
  $factory = new React\MySQL\Factory();

• Improve test setup, use GitHub actions for continuous integration (CI) and fix minor typo.
  (#132 by @SimonFrings and #129 by @mmoreram)