Returning details immediately after inserting into database

[LawEKS]

@hannahcmtucker mentioned in gitter a way to return values from a table after you have inserted into it.

const query = {
  text: `INSERT INTO users(username, password) VALUES($1, $2) RETURNING USERNAME, ID`,
  values: [username, password]
}

We can use this when we are creating a comment. Where we need to get a destination id but have insert a destination if it does not exist in the destinations table.