Ability to manipulate $header and $footer from within the omniture_variables hook.

On line 122 of omniture.module, I added $header and $footer as follows:

if ($omniture_hooked_vars = module_invoke_all('omniture_variables', $main, $header, $footer)) {

Now I am able to append, prepend and manipulate the $header and $footer values as needed from within my custom method, like so:

function myhelper_omniture_variables($main, $header, $footer) {

  $data = array();

  // Add the Omniture account variable that's been abstracted from Omniture's JS code to the beginning of $header, if it exists.
  // Note: I added 'omniture_account' as a variable in this module since I've removed it from the s_code.js file.
  if ($s_account = variable_get('omniture_account', false)) {
    $data['header'] = '<script type="text/javascript" language="JavaScript">' . PHP_EOL
      . 'var s_account = "' . $s_account . '";' . PHP_EOL
      . '</script>' . PHP_EOL
      . $header;
  }

  // Add some more useful code to the end of $header.
  $data['header'] .= 'more useful code';

  // Add some useful code to the beginning of $footer as well as the end of $footer.
  $data['footer'] = 'useful code ' . PHP_EOL . $footer . PHP_EOL . ' more useful code at the end';

  return $data;
}