Rings of stealth and elven cloaks identify like elven boots

Before this, rings of stealth would never auto-identify when worn, and
elven cloaks would be identified when worn no matter the stealthiness of
the character.

Now, rings of stealth and elven cloaks auto-identify when:

 1. they grant stealth to an otherwise unstealthy character when worn.
 2. they take away stealth from an otherwise unstealthy character when
    taken off.

These are the same circumstances that elven boots auto-identify.