add admin model for student (need to be able to see activation keys in db)

lms/djangoapps/student/admin.py

+'''
+django admin pages for courseware model
+'''
+
+from student.models import *
+from django.contrib import admin
+from django.contrib.auth.models import User
+
+admin.site.register(UserProfile)
+
+admin.site.register(Registration)
+
+admin.site.register(PendingNameChange)
+