Tags override support (#259)

tests/reference.yaml

@@ -761,7 +761,7 @@ paths:
             items:
               $ref: '#/definitions/UserSerializerrr'
       tags:
-        - users
+        - Users
     post:
       operationId: users_create
       description: apiview post description override
@@ -787,7 +787,7 @@ paths:
               username:
                 type: string
       tags:
-        - users
+        - Users
       security: []
     patch:
       operationId: users_dummy
@@ -797,7 +797,7 @@ paths:
         '200':
           description: ''
       tags:
-        - users
+        - Users
     parameters: []
   /users/{id}/:
     get:
@@ -814,7 +814,7 @@ paths:
           schema:
             $ref: '#/definitions/UserSerializerrr'
       tags:
-        - users
+        - Users
     put:
       operationId: users_update
       description: user_detail fbv docstring
@@ -830,7 +830,7 @@ paths:
           schema:
             $ref: '#/definitions/UserSerializerrr'
       tags:
-        - users
+        - Users
     parameters:
       - name: id
         in: path