Adds MySQL syntax to Values builder

[belchior]

Basic API

// Insert builder
let query = sql::Insert::new()
  // one of is required
  .values("('foo', 'Foo')")
  .row("('foo', 'Foo')")
  .as_string();

// Values builder
let query = sql::Values::new()
  .row("(1, 'one')")
  .as_string();

Reference

• https://dev.mysql.com/doc/refman/8.4/en/values.html
• https://dev.mysql.com/doc/refman/8.4/en/insert.html