Fixed AIOOBE and a missing return, removed an unused and ambiguous method from CommandContext.

src/main/java/com/sk89q/minecraft/util/commands/CommandContext.java

@@ -221,10 +221,6 @@ public class CommandContext {
         return Double.parseDouble(value);
     }
 
-    public int length() {
-        return args.length;
-    }
-
     public int argsLength() {
         return args.length - 1;
     }