Support for where conditions with tuples of values

[YarekTyshchenko]

Postgres supports syntax like this: ... WHERE (a, b) in ((1, 2), (3, 4))
It would be nice to pass Seq of Tuple (or even a case class) as a Param in the query, currently it seems to only work with String.

A test for something like this (for sql"" syntax) might look something like this:

"Seq of tuple params for IN operator" in {
  val p1 = Seq(("foo", "bar"), ("three", "four"))
  expectQuery("SELECT * FROM foo WHERE (a, b) IN (($1, $2), ($3, $4))", "foo", "bar", "three", "four") {
    sql"SELECT * FROM foo WHERE a IN ($p1)"
  }
}