Switch to python-ldap

pyldap is deprecated and merged with python-ldap, so we should depend
on it directly instead of the deprecated wrapper. For details see
https://pypi.org/project/pyldap/

Change-Id: I2c8ee2c792a476fe12c234a55af24144e6b511cd
Depends-On: https://review.openstack.org/#/c/582973/

doc/requirements.txt

@@ -6,5 +6,5 @@ sphinx!=1.6.6,!=1.6.7,>=1.6.2 # BSD
 sphinxcontrib-apidoc>=0.2.0  # BSD
 reno>=2.5.0 # Apache-2.0
 os-api-ref>=1.4.0 # Apache-2.0
-pyldap>=2.4.20 # PSF
+python-ldap>=3.0.0  # PSF
 ldappool>=2.0.0 # MPL

lower-constraints.txt

@@ -92,7 +92,7 @@ pycparser==2.18
 pyflakes==0.8.1
 Pygments==2.2.0
 pyinotify==0.9.6
-pyldap===2.4.20
+python-ldap===3.0.0
 pymongo===3.0.2
 PyMySQL==0.8.0
 PyNaCl==1.2.1

releasenotes/notes/use-python-ldap-0318ff7798bdd98d.yaml

@@ -0,0 +1,6 @@
+---
+upgrade:
+  - Keystone now relies on python-ldap instead of pyldap.
+    The pyldap library is a deprecated fork from python-ldap. Starting
+    with python-ldap 3.0 release this has been merged and is maintained
+    there.

setup.cfg

@@ -28,7 +28,7 @@ packages =
 
 [extras]
 ldap =
-  pyldap>=2.4.20 # PSF
+  python-ldap>=3.0.0 # PSF
   ldappool>=2.0.0 # MPL
 memcache =
   python-memcached>=1.56 # PSF