docs: ecosystem/integrations update 2 (#5282)

# docs: ecosystem/integrations update 2

#5219 - part 1 
The second part of this update (parts are independent of each other! no
overlap):

- added diffbot.md
- updated confluence.ipynb; added confluence.md
- updated college_confidential.md
- updated openai.md
- added blackboard.md
- added bilibili.md
- added azure_blob_storage.md
- added azlyrics.md
- added aws_s3.md

## Who can review?

@hwchase17@agola11
@agola11
 @vowelparrot
 @dev2049

docs/integrations/diffbot.md

@@ -0,0 +1,18 @@
+# Diffbot
+
+>[Diffbot](https://docs.diffbot.com/docs) is a service to read web pages. Unlike traditional web scraping tools, 
+> `Diffbot` doesn't require any rules to read the content on a page.
+>It starts with computer vision, which classifies a page into one of 20 possible types. Content is then interpreted by a machine learning model trained to identify the key attributes on a page based on its type.
+>The result is a website transformed into clean-structured data (like JSON or CSV), ready for your application.
+
+## Installation and Setup
+
+Read [instructions](https://docs.diffbot.com/reference/authentication) how to get the Diffbot API Token.
+
+## Document Loader
+
+See a [usage example](../modules/indexes/document_loaders/examples/diffbot.ipynb).
+
+```python
+from langchain.document_loaders import DiffbotLoader
+```