Changes:
- Initalize Aria early to allow it to load mysql.plugin table with --help
- Don't print 'aborting' when doing --help
- Don't write 'loose' error messages on log_warning < 2 (2 is default)
- Don't write warnings about disabled plugings when doing --help
- Don't write aria_log_control or aria log files when doing --help
- When using --help, open all Aria tables in read only mode (safety)
- If aria_init() fails, do a cleanup(). (Frees used memory)
- If aria_log_control is locked with --help, then don't wait 30 seconds
  but instead return at once without initialzing Aria plugin.