Add a constructor that takes a single Stat, for some msoy Passport code being worked on

git-svn-id: svn+ssh://src.earth.threerings.net/vilya/trunk@720 c613c5cb-e716-0410-b11b-feb51c14d237

src/java/com/threerings/stats/data/StatSet.java

@@ -38,12 +38,24 @@ public class StatSet extends DSet<Stat>
         public void updateStats (Stat stat);
     }
 
+    /** Creates a stat set with the specified contents. */
+    public StatSet (Iterable<Stat> contents)
+    {
+        super(contents);
+    }
+
     /** Creates a stat set with the specified contents. */
     public StatSet (Iterator<Stat> contents)
     {
         super(contents);
     }
 
+    /** Creates a stat set with the specified contents. */
+    public StatSet (Stat stat)
+    {
+        add(stat);
+    }
+
     /** Creates a blank stat set. */
     public StatSet ()
     {