Eliminate config file warnings for setting default values
Use bind_ip for node health check in mongod provider
Set Chef version at driver level
Add authentication support for single nodes and replica sets

Includes a new provider (user) for setting up new users for a database,
which is then used by other providers to create a default admin user,
if authentication support is enabled.
Also added support for creating and using a key file in replica sets.
Tests for auth support in both single node and replica set scenarios
Fix for FoodCritic failure on conditional execution
Add basic documentation for authentication support