def switch_to_workspace(target_workspace)
      if target_workspace == 'next'
        target_workspace = Wmctile.current_workspace + 1
      elsif target_workspace == 'previous'
        target_workspace = Wmctile.current_workspace - 1
      elsif target_workspace == 'history'
        # must be -2 as -1 is the current workspace
        target_workspace = Wmctile.memory.get(:workspace_history)[-2]
      end
      system "wmctrl -s #{target_workspace}"
      target_workspace
    end
def switch_to_workspace(target_workspace)
      if target_workspace == 'next'
        target_workspace = Wmctile.current_workspace + 1
      elsif target_workspace == 'previous'
        target_workspace = Wmctile.current_workspace - 1
      elsif target_workspace == 'history'
        # must be -2 as -1 is the current workspace
        target_workspace = Wmctile.memory.get(:workspace_history)[-2]
      end
      system "wmctrl -s #{target_workspace}"
      target_workspace
    end
Switch to target_workspace.

 @param [String] target_workspace Target workspace index or "next"/"previous".

 @return [Integer] Target workspace number