Remove the idea of operation label actions

Some code pieces why I think this needs work:

commit_restrictions/commit_restrictions.module: assumes operation labels have action

 foreach ($operation['labels'] as $label) {
   if ($label['action'] != VERSIONCONTROL_ACTION_DELETED) {
     return FALSE;
   }
 }

includes/VersioncontrolOperation.php: some code(never used? :-/) is hardcoding the action data member

    foreach ($this->labels as $label) {                                       
      // first, ensure there's a record of the label already                  
      if (!isset($label->label_id)) {                                         
        $label->insert();                                                     
      } 
      $values = array(
        'vc_op_id' => $this->vc_op_id,
        'label_id' => $label->label_id,
        // FIXME temporary hack, sets a default action. _CHANGE_ this.        
        'action' => !empty($label->action) ? $label->action : VERSIONCONTROL_ACTION_MODIFIED,
      );
      $insert->values($values);                                               
    }

includes/controllers.inc: labels inside operations still have action data member

  protected function extendData(&$queried_entities) {
    parent::extendData($queried_entities);
    $query = db_select('versioncontrol_operations', 'vco');
    $query->join('versioncontrol_operation_labels', 'vcol', 'vco.vc_op_id = vcol.vc_op_id');
    $query->join('versioncontrol_labels', 'vcl', 'vcol.label_id = vcl.label_id');
    $query->fields('vco', array('vc_op_id'))
      ->fields('vcol', array('action'))
      ->fields('vcl'); // add all the label fields
    // build the constraint list
    $operation_ids = array();
    foreach ($queried_entities as $entity_data) {
      $operation_ids[] = $entity_data->vc_op_id;
    }
    $result = $query->condition('vco.vc_op_id', $operation_ids)
      ->execute();

    // Attach each label to the labels array on the respective operation data.
    foreach ($result as $label) {
      $label->repository = $this->options['repository'];
      $queried_entities[$label->vc_op_id]->labels[$label->name] = $this->backend
        ->buildEntity($label->type === VERSIONCONTROL_LABEL_BRANCH ? 'branch' : 'tag', $label);
    }
  }

Not ready before hard code-freeze, so changing tag.

After taking a look about what those pieces of code were doing, I end up thinking that decouple it independently will help.

I have done that: I am introducing a new entity, VersioncontrolOperationLabel, which will have the action mentioned here.

I am also attaching the git backend change here con convienience at review time.

@sdboyer: Please let me know your opinion before actually pushing these patches.

After a quick IRC talk, I end up agreeing sdboyer point, but this involves chnage db schema to remove action from there too.

I will provide a patch for that.

Better title

Ok, here it is the commit patch I pushed :-)