Enable use of CRL (and more) in verify context. (#483)

* Enable use of CRL (and more) in verify context.

* flake8 fixes.

* Comments from Hynek & Paul.

* More updates from Paul & Hynek.

* Fix closing backtick.

* Remove commented out constants.

* More doc updates. Changelog update.

* Getting closer?

* Sphinx fix.

* Indent docstring.

* More Sphinx updates.

* Type updates for docstrings.

* Remove Enum subclassing.

* Docstring update.

* Docstrings updates.

* Round and round it goes. Where it ends, nobody knows.

* Remove TODO comment. Need @sholsapp to follow up.

* Time for lots of alcohol.
diff --git a/doc/api/crypto.rst b/doc/api/crypto.rst
index 7597d7f..5f7df24 100644
--- a/doc/api/crypto.rst
+++ b/doc/api/crypto.rst
@@ -206,6 +206,25 @@
 
 .. _openssl-pkey:
 
+X509StoreFlags constants
+------------------------
+
+.. autoclass:: X509StoreFlags
+
+    .. data:: CRL_CHECK
+    .. data:: CRL_CHECK_ALL
+    .. data:: IGNORE_CRITICAL
+    .. data:: X509_STRICT
+    .. data:: ALLOW_PROXY_CERTS
+    .. data:: POLICY_CHECK
+    .. data:: EXPLICIT_POLICY
+    .. data:: INHIBIT_MAP
+    .. data:: NOTIFY_POLICY
+    .. data:: CHECK_SS_SIGNATURE
+    .. data:: CB_ISSUER_CHECK
+
+.. _openssl-x509storeflags:
+
 PKey objects
 ------------