Settings menu contains a "short url" action when the extension is not activated

[Kit Blake]

From the s-g list:
"I noticed that in the SMI, the 'Settings' menu contains a "short url" action. A default install displays this action, but it raises an "Internal Server Error". I had to go to the extensions service and activate the "silva short urls" extension before this action would work."

Apparently the menu option is always available while it should only show up if the extension is activated.

[Sylvain Viollon (thefunny)]

The code for the SMI screens now properly implement the available methods. This was done incorrectly, not on the correct classes (with broken python).