Control panel should show numbers in each population

It's quite difficult to determine the number of cells in a generated network, and especially if you set a cell density you're never sure of the total number in an instance of the network. A good place for this would be the Control Panel, where you can list the instances if you expand the individual cell populations. What would be better is if the number in each population was visible beside the name, and mayne the total at network e.g.

> network (30)
  > E2 (6)
  > L1 (3)
...

首先定位 Control Panel 及其網路和細胞群體清單元件。查看目前如何表示群體實例和細胞數量，然後按照 issue 中的顯示方式，在每個群體旁邊以及網路旁邊新增數量。完成標準是：展開的項目顯示群體數量，網路顯示其總數。