anchor.diff:  
   == Group API
   
  -=== Instance methods
  -
  -==== getID() : int
  -
  -Returns the unique *id* of the group.
  -
  +=== Name
   
   ==== getName() : string
   
   Returns the *name* of the group.
  -
  -
  -==== getDescription() : string
  -
  -Returns the *description* of the group.
   
   
   ==== setName(string $name) : void
  
positive.code: Updates the group's *name* in the database.
  Throws a *GroupException* with code *202* if '$name' is invalid, *203* if unavailable.
  See *validName()* & *availableName()* for more details.
  
  
  ==== setDescription(string $description) : void
  
negative.code: ==== getUserGroups(User $user) : array
  
  Returns an array of *Group* objects representing all groups which '$user' is a member of.
  
  
  ==== validDescription(string $description) : bool
  