WL#5349: Change default storage engine to InnoDB

As of MySQL 5.5, the default storage engine should change from MyISAM to InnoDB.

InnoDB should be the default storage engine for all user created objects in the
regular and enterprise versions of MySQL. 

MyISAM will remain the default engine for the embedded server.

System tables will still remain in MyISAM tables

InnoDB code should be mandatory in the build (except for the embedded server),
so it should not be possible to exclude InnoDB support when building MySQL server.

Upgrade/downgrade scenarios should not be affected by this change.  If a table
is MyISAM before upgrade/downgrade, it should continue to be so.

The regression test suite will need to be examined and changed to ensure that
MyISAM related regression tests have an explicit "engine=MyISAM" clause. Since
MyISAM so far has been the default, some of these test cases may have omitted
the engine clause.

Change the following default values: (as per recommendations from the InnoDB team)
  innodb_file_format    -> Barracuda  (was: Antelope)
  innodb_strict_mode    -> TRUE (was: FALSE)
  innodb_file_per_table -> TRUE (was: FALSE)

Note: the changes to the default values were reverted back in 5.5 due to
replication failures.