def get_plugin(namespace, plugin_type, plugin_name)
    namespace    = namespace.to_sym
    plugin_type  = sanitize_id(plugin_type)

    instances    = get_hash([ :active_info, namespace, plugin_type ])
    instance_ids = array(@instance_map.get([ namespace, plugin_type, plugin_name.to_s.to_sym ]))

    if instance_ids.size
      return instances[instance_ids[0]]
    end
    nil
  end
def get_plugin(namespace, plugin_type, plugin_name)
    namespace    = namespace.to_sym
    plugin_type  = sanitize_id(plugin_type)

    instances    = get_hash([ :active_info, namespace, plugin_type ])
    instance_ids = array(@instance_map.get([ namespace, plugin_type, plugin_name.to_s.to_sym ]))

    if instance_ids.size
      return instances[instance_ids[0]]
    end
    nil
  end
Return a plugin instance by name if it exists

 * *Parameters*
   - [String, Symbol] *namespace*  Namespace that contains the plugin
   - [String, Symbol] *plugin_type*  Plugin type name
   - [String, Symbol] *plugin_name*  Plugin name to return

 * *Returns*
   - [nil, Nucleon::Plugin::Base]  Returns a plugin instance of name specified if it exists

 * *Errors*

 See:
 - Nucleon::Plugin::Base
 - Nucleon::Config#get_hash

 See also:
 - #sanitize_id