API changes
===========

- Added level parameter to logging:new so that a default starting level can
  be set by caller. For example:
    
    local log = logging.my_appender(logging.INFO)
    
- Added LEVEL_H and LEVEL_A arrays as global

- Arranged so that level() functions are dummies for all levels below the above

- Added getLevel function

- Added isDebug function

Bug fixes
=========

- tonumber added to "import" list on top of logging.lua; it's used by tostring()