[WIP] coerce types for config parameters; add missing config parameters recognized by TinyTDS -- Issue #740

coerce types for config parameters; add missing config parameters recognized by TinyTDS -- Issue #740 see also: https://github.com/rails-sqlserver/tiny_tds/issues/461

changed to [WIP] to add unit tests for additional parameters and checks for the type coercion expected values

@PaulCharlton do you need help with this?

@wpolicarpo thanks for asking! --- it has been more of a bandwidth issue and getting distracted with other things -- if you need it sooner, by all means add some additional commits