This method expects asceding integer values as the keys, which map to the appropriate
columns. Currently, there is no special "header" option, but you can define them for your
own.
Example Usage:
$output = array(
array('Name', 'Age'),
array('----', '---'),
);
foreach($users as $user) {
$output[] = array($user->name, $user->age);
}
$this->columns($output);
Would render something similar to:
Name Age
---- ---
Jane Doe 22
Foo Bar 18
This method also calculates the needed space between the columns. All option params given
also get passed down to the out() method, which allow custom formatting. Passing something
like $this->columns($output, array('style' => 'red) would print the table in red.