Permissions not saved

Issue Summary

After installing the module, I found that permissions were not being saved. I tracked it down to a minor issue in the form api implementation. Previously the code was using $form['#submit'] to define the submit handler for this module, but the '#submit' key is an attribute of the submit form type to indicate whether a button submits the form, according to the api. So I've created a simple patch here that applies the submit handler via hook_taxonomy().