Allow setting ClientControls/decoder when using a connection string #509

Is your feature request related to a problem? Please describe.

I only have a connection string to connect to the database, so I cannot create a ClientOptions instance with individual fields (database, hostname, user, password, etc) - I just don't have those values. However, ClientControls is a field on ClientOptions, instead of being a separate parameter of the Client/Pool constructors. This means I cannot change decoder settings, which I need to do (I want to set decodeStrategy to "string", as I want to manually use Temporal in place of the default Date handling).

Describe the solution you'd like

Provide overloads for the constructors of Client and Pool that take both a connection string and a ClientControls instance.

Describe alternatives you've considered

• Pick apart my connection string manually to extract the values I need. Duplicates work that deno-postgres is already doing.
• Specify ::text for every selected column, hacking around the automatic type conversions. Noisy and error-prone.