"Freezing" Menu Item on the Left When Selected?

[LeoNerdoG]

If user navigates to some service that he selects on the left side (e.g. Wire graph), that item does not get "non-selectable", so if user creates a component or changes something without applying changes or saving configuration and then clicks the menu item on the elft again, Kura shows info message for discarding changes - I think we should make selected menu item on the left non-selectable after user navigates to it, just to avoid confusion.

Testflow:

1. Login to Kura as admin/admin
2. Go to WireGraph and create a component (e.g. timer) without saving it
3. On the left side click on "Wire Graph"
4. Observe the info message from Kura (Changes not saved)

Expected behavior Menu item on the left should be "non selectable" if user is currently here (in this case Wire Graph").

Screenshots /

Target Environment (please complete the following information): Board: Raspberry Pi 3 OS version: Linux raspberrypi 4.19.75-v7+ # 1270 SMP Tue Sep 24 18:45:11 BST 2019 armv7l GNU/Linux Additional info: /