Named parameter binding support

Hi all,

I've attached a patch that adds support for named parameter binding when calling procedures or functions. Applications can use SQLSetDescField to specify parameter names, as described at https://docs.microsoft.com/en-us/sql/odbc/reference/develop-app/binding-parameters-by-name-named-parameters

Notes:

* Works for input and output parameters

* Regression tests enhanced to include binding parameters by name

Regards,