Implement `queryWithNamed`

[oishikg]

Currently, the PgNamed library has no named parameter implementation for queryWith. Implementing a queryWithNamed would be very helpful, since we could use it as part of the refactoring in this issue, and for future functions which need to use a user defined row parser.

[chshersh]

@oishikg You can open PR to this repo with the implementation of this function

[oishikg]

@chshersh , thanks for the comment, I've done this! See #17