WL#8313: Set ROW based binary log format by default

Affects: Server-5.7   —   Status: Complete

This work changes the default of binlog-format to "ROW" (was: STATEMENT). 

Row format provides safe logging in all cases, and allows for improved InnoDB
locking semantics. 

See also:

In response to feedback, we have decided to not change transaction_isolation at 
this point in time.