Limit the Skychay UI to localhost

[Senyoret1]

Changes:

• Now the SkychatUI can only been opened from localhost or 127.0.0.1.

How to test this PR:
Recompile the UI and use it to open the Skychat UI. It will open it from 127.0.0.1.

Note: should this behaviour be configurable?

[0pcom]

I think we need to change this in either pkg/skyenv or pkg/visor/visorconfig. Basically it needs to populate in the config as localhost:8001 ; just to match what we have for other apps more or less

i believe it's configurable for skywire-cli config update but need to check it

[Senyoret1]

The last commit adds a modal window were the user can select if it should be posible to access Skychat outside localhost and also allows to change the port.

@0pcom With this change, the config file need no modifications. If the config file has :8001, you can only access from localhost, but if the config file has *:8001, you can access from outside localhost, as before. Is there a a part of the CLI where that should be documented?

[Senyoret1]

The last commit ask for confirmation before allowing the user to open the access to the Skychat app outside localhost.