Fix requirements versions to work around a few issues...

requirements.txt

@@ -1,5 +1,5 @@
 Django>=1.8.17,<1.9
-psycopg2==2.5.2
+psycopg2==2.5.4
 python-ldap==2.4.15
 wsgiref==0.1.2
 python-dateutil==2.2
@@ -10,10 +10,11 @@ django-polymorphic==0.7.2
 django-sendfile==0.3.10
 django-localflavor==1.1
 django-netfields>=0.4,<0.5
-django-ldapdb>=0.4.0,<5.0
+django-ldapdb>=0.4.0,<0.5.0
 django-multiselectfield>=0.1.5
 feedparser
 six==1.10.0
 WeasyPrint==0.31
 freezegun==0.3.8
-django-registration==2.2
+django-registration>=2.4,<2.5
+pyldap<3.0