nmtui.md: add page (#1613)

pages/linux/nmtui.md

@@ -0,0 +1,24 @@
+# nmtui
+
+> Text user interface for controlling NetworkManager.
+> Use arrow keys to navigate, enter to select an option.
+
+- Open the user interface:
+
+`nmtui`
+
+- Show a list of available connections, with the option to activate or deactivate them:
+
+`nmtui connect`
+
+- Connect to a given network:
+
+`nmtui connect {{name|uuid|device|SSID}}`
+
+- Edit/Add/Delete a given network:
+
+`nmtui edit {{name|id}}`
+
+- Set the system hostname:
+
+`nmtui hostname`