…r for working with sentinel setups (StackExchange#1427) Fix issue with duplicate endpoints being added in the UpdateSentinelAddressList method (StackExchange#1430).

Add string configuration overloads for sentinel connect methods. Remove password from sentinel servers as it seems the windows port does not support it. Add some new tests.

Co-authored-by: Nick Craver <nrcraver@gmail.com>

…e. Make SentinelMasterConnect private.