systematic use of from __future__ import absolute_import. it eliminates import NAME confusion with very common names (eg. import ldap is very ambiguous: can be a ldap module from realms-wiki, a ldap module from flask-ldap-login, or python-ldap module.

also cleant up a bit the import towards PEP8: builtin modules first, then 3rd party python packages, then local packages

realms/lib/util.py

@@ -1,4 +1,5 @@
-import click
+from __future__ import absolute_import
+
 import re
 import os
 import hashlib
@@ -6,6 +7,8 @@ import json
 import string
 import random
 import sys
+
+import click
 from jinja2 import Template