scalability: fix missing imports

scalability_test/__init__.py

 import os.path
+import re
+import glob
 import json
 import urlparse
 
+HERE = os.path.dirname(__file__)
+BT5 = os.path.join(os.path.split(HERE)[0],'bt5')
+
 ZOPE_USER_FAMILY = "user"
 ZOPE_ACTIVITIES_FAMILIY = "activities"
 PERSON_KEY = "person_per_hour"