Fixed a problem with `default` becoming the name of some enumerations.

The `Enumerations` class uses reflection to determine the name of an
enumeration. This sometimes (because of initialization order) results in
an enumeration being named `default`.

An example:

    object T extends Enumeration {
      val a, b = Value
      val default = a
    }

    println(T.a) // might print "default"