Turns out we shouldn't call it uniqueIdentifier (#3234)

http://www.ca.com/us/services-support/ca-support/ca-support-online/knowledge-base-articles.tec465360.html
diff --git a/docs/x509/reference.rst b/docs/x509/reference.rst
index eda0581..bc408ae 100644
--- a/docs/x509/reference.rst
+++ b/docs/x509/reference.rst
@@ -2306,7 +2306,7 @@
 
         Corresponds to the dotted string ``"2.5.4.44"``.
 
-    .. attribute:: UNIQUE_IDENTIFIER
+    .. attribute:: X500_UNIQUE_IDENTIFIER
 
         .. versionadded:: 1.6
 
diff --git a/src/cryptography/x509/oid.py b/src/cryptography/x509/oid.py
index a7e41d5..5e60f9f 100644
--- a/src/cryptography/x509/oid.py
+++ b/src/cryptography/x509/oid.py
@@ -107,7 +107,7 @@
     GIVEN_NAME = ObjectIdentifier("2.5.4.42")
     TITLE = ObjectIdentifier("2.5.4.12")
     GENERATION_QUALIFIER = ObjectIdentifier("2.5.4.44")
-    UNIQUE_IDENTIFIER = ObjectIdentifier("2.5.4.45")
+    X500_UNIQUE_IDENTIFIER = ObjectIdentifier("2.5.4.45")
     DN_QUALIFIER = ObjectIdentifier("2.5.4.46")
     PSEUDONYM = ObjectIdentifier("2.5.4.65")
     DOMAIN_COMPONENT = ObjectIdentifier("0.9.2342.19200300.100.1.25")
@@ -189,7 +189,7 @@
     NameOID.GIVEN_NAME: "givenName",
     NameOID.TITLE: "title",
     NameOID.GENERATION_QUALIFIER: "generationQualifier",
-    NameOID.UNIQUE_IDENTIFIER: "uniqueIdentifier",
+    NameOID.X500_UNIQUE_IDENTIFIER: "x500UniqueIdentifier",
     NameOID.DN_QUALIFIER: "dnQualifier",
     NameOID.PSEUDONYM: "pseudonym",
     NameOID.DOMAIN_COMPONENT: "domainComponent",