Clean-up some delimiter escaping issues.
Clean-up some delimiter escaping issues.

Simplify parsing by fulling parsing the RI without processing the
fields. The sub-fields are then properly processed as needed.

Add the ability to state driver parameters by specifying a setting in square
brackets. For instance: "pq://host/db?[driver_param]=value". This provides a
means for users to state and clearly identify parameters intended for the
driver(notably, the server_encoding hint).

Properly escape delimiters in sub-fields when serializing the string.

python-postgres/fe,python-postgres/fe