Fix TPS highlight box not moved along with ruler in another plotting widget

closes #242 (closed)

• Fix this by calling to calculate 5m block index, displaying info and highlighting ruler box from super class on_button_press_event()'s loop through all peer_plotting_widgets.
• Optimize code by making sure no redundancy in calculating for 5m block index and displaying info.

Ex: 6407.sdr, channel LH1's TPS, time from the start of on_pick_event() until end of on_ctrl_cmd_click():

• develop branch: 0.6104s
• This branch: 0.2269s