feat(docs) Add autogeneration notices

api-docs/generator.py

@@ -289,6 +289,8 @@ def dump_markdown(path, data):
         pass
     with open(path, 'w') as f:
         template = u"""---
+# This file is automatically generated from the API using `api-docs/generate.py`
+# Do not manually this file.
 {}
 ---
 """

src/sentry/templates/sentry/apidocs/index.md

@@ -1,4 +1,6 @@
 ---
+# This file is automatically generated from the API using `api-docs/generate.py`
+# Do not manually edit this file.
 title: {{ title }}
 ---