Allow drush make to package dragresize properly

Drupal projects would benefit from this plugin.  Using drush make, one cannot currently put the plugin in the correct directory for ckeditor because the project versions the plugins/dragresize folder.

Using:
libraries[dragresize][download][type] = "get"
libraries[dragresize][download][url] = "https://github.com/sstur/ck-dragresize/archive/master.zip"
libraries[dragresize][destination] = "libraries/ckeditor/plugins"

Currently drush make will download the library files and put them in a double-nested directory:  e.g., /libraries/ckeditor/plugins/dragresize/plugins/dragresize/plugin.js

If the plugin files were in the root directory of this repository, then drush make would download and place them correctly: e.g., /libraries/ckeditor/plugins/dragresize/plugin.js