Support for DBI hosts and groups
It's just  a draft feature
   groups_dbi($dsn, $user, $password, $sql)
         With this function you can read groups from DBI source.

    Example: groups_dbi( 'DBI:mysql:rex;host=db01', 'username', 'password',
    "SELECT * FROM HOST");
    Database sample for MySQL
         CREATE TABLE IF NOT EXISTS `HOST` (
        `ID` int(11) NOT NULL,
        `GROUP` varchar(255) DEFAULT NULL,
        `HOST` varchar(255) NOT NULL,
        PRIMARY KEY (`ID`),
        UNIQUE KEY `HOST` (`HOST`)
        );

    Data sample for MySQL
         INSERT INTO `HOST` (`ID`, `GROUP`, `HOST`) VALUES
        (1, 'db', 'db01'),
        (2, 'db', 'db02'),
        (3, 'was', 'was01'),
        (4, 'was', 'was02');
Removing Data::Dumper call
Adding support for all group
Removing unique key in DBI.pm to support ahost in multiple group.
YAML lookup Support
all group support
Removing Data::Dumper calls
- #346 added files to tests
- #346 rewrote groups_db and groups_yaml to have same syntax as other groups_* function.
- #346 rewrite DBI Helper to make only one connection on multiple calls