- Complete rewrite.
- Added a new option in 'port' to define the number of graphs per row.
- Fixed a missing description in the first entry of each network interface in
  the options list.
- Fixed a missing argument on each *_init() function preventing show an "Ok"
  message when debugging is enabled.
- Fixed some bugs in Groups.
- Fixed a typo in the percentage variable in FS alert.
- Fixed variables naming in 'mail' graph when using Postfix MTA that prevented
  to see the values bounced, discarded and forwarded.
- Fixed a number of small bugs.