MONGOID-5106 Remove usage of private driver code (#5002)

Author: comandeo-mongo

source/reference/configuration.txt

@@ -177,7 +177,7 @@ can be configured.
           connect: :direct
 
           # Change the default time in seconds the server monitors refresh their status
-          # via ismaster commands. (default: 10)
+          # via hello commands. (default: 10)
           heartbeat_frequency: 10
 
           # The time in seconds for selecting servers for a near read preference. (default: 0.015)