def inherited(subclass)
      subclass._arguments = []
      subclass._description = ''
      subclass._abstract = false
      subclass._skip_options = false
      subclass._exe_name = @_exe_name
      subclass._default_priority = @_default_priority.to_f / 2
      subclass._priority = 0
      super
    end
def inherited(subclass)
      subclass._arguments = []
      subclass._description = ''
      subclass._abstract = false
      subclass._skip_options = false
      subclass._exe_name = @_exe_name
      subclass._default_priority = @_default_priority.to_f / 2
      subclass._priority = 0
      super
    end
Trigger when a class inherit this class
 Rest class_attributes that should not be shared with subclass
 @param subclass [Clin::Command]