DryIcons folders, SocialShift existance validation

It took me some time investigating to find out that in order for DryIcons to be found, the following is needed:

1. 1. In /icons/dryicons/ folder one should first make PNG folder, make sure on case sensitive servers you do need CAPITALS (the way it is in code but not in library!)
2. 2. All pngs should be grouped in folders according to size and this command will help you in copying there: while you are in /icons/dryicons/PNG issue this command and change part number cp -a ../socialize-part-2-icons-set/* . and you will have all parts in PNG folder.

I think maintainer should lowercase png folder and make better explanation because people do like to use options thay are offered and it is hard (impossible) to figure this out for less inclined.

SocilaShift icons need change in $pt otherwise library won't be recognized, just this line added to end of array, 'twitter' => 'Twitter', or here is whole function:

 function socialmedia_icon_path_instantshift($platform = 'twitter', $style = NULL) {
  $style = isset($style) ? $style : '32';
  $pt = array(
    'delicious' => 'del.icio.us',
    'email' => 'mail',
    'googleplus' => 'buzz',
    'lastfm' => 'last_fm',
    'stumbleupon' => 'StumbleUpon',
    'twitter' => 'Twitter',
  );
  $path = drupal_get_path('module', 'socialmedia') . '/icons/instantshift/' . $style . '/' . ((isset($pt[$platform]))? $pt[$platform] : $platform) . '.png'; 
  return $path;
}