Add a test for recovery when toggling logging on and off.

refs SERVER-16692

--HG--
rename : test/suite/test_txn02.py => test/suite/test_txn09.py
Fix recovery if logging is turned off, changes are made and checkpointed, then the database is reopened with logging turned on.

refs SERVER-16692
Don't run recovery if restarting after a checkpoint taken with logging disabled.

While in the area, rename macros to have a "WT_" prefix.

refs SERVER-16692
update unused defines
Merge pull request #1523 from wiredtiger/log-toggling

Test and fix recovery with logging toggled on and off
Reword comment a bit.