* Switch to using redis modules for task table.
* Switch to using redis modules for the task table.
* Fix some tests.
* Fix naming and remove code duplication.
* Remove duplication in redis modules and add more cleanups.
* Address comments.
* Set logging levels in Makefile using -DRAY_COMMON_LOG_LEVEL=level
* Lower level of some LOG_ERROR messages, log the name of the table operation on failure
* Address rest of Robert's comments
* Fix spurious log message
* Merge task table and task log
* Fix test in db tests
* Address Robert's comments and some better error checking
* Add a LOG_FATAL that exits the program