Incorrect display of Close Command Center and Open Command Center in Tools Menu

[brandesNW]

The problem is that the Tools menu is not updated when a closed command center is opened by Jump to Command Center or opening a new model

To reproduce: Version 1

1. Open NetLogo (or just have the command center open, and Close Command Center visible in the Tools menu)
2. Close command center via Tools-> Close Command Center or hotkey (ctrl-\ or cmd-\)
3. Jump to command center via Tools-> Jump to Command Center or hotkey (ctrl-shift-C or cmd-shift-C)

The Command Center will now be open, but the Tools menu choice is Open Command Center

To reproduce: Version 2

1. Open NetLogo
2. Close command center via Tools-> Close Command Center or hotkey (ctrl-\ or cmd-\)
3. Open a new model

The Command Center will now be open, but the Tools menu choice is Open Command Center