docs: add Shale Protocol integration guide (#5814)

This PR adds documentation for Shale Protocol's integration with
LangChain.

[Shale Protocol](https://shaleprotocol.com) provides forever-free
production-ready inference APIs to the open-source community. We have
global data centers and plan to support all major open LLMs (estimated
~1,000 by 2025).

The team consists of software and ML engineers, AI researchers,
designers, and operators across North America and Asia. Combined
together, the team has 50+ years experience in machine learning, cloud
infrastructure, software engineering and product development. Team
members have worked at places like Google and Microsoft.

#### Who can review?

Tag maintainers/contributors who might be interested:

  - @hwchase17
  - @agola11

---------

Co-authored-by: Karen Sheng <46656667+karensheng@users.noreply.github.com>

docs/integrations/shaleprotocol.md

@@ -0,0 +1,43 @@
+# Shale Protocol
+
+[Shale Protocol](https://shaleprotocol.com) provides production-ready inference APIs for open LLMs. It's a Plug & Play API as it's hosted on a highly scalable GPU cloud infrastructure. 
+
+Our free tier supports up to 1K daily requests per key as we want to eliminate the barrier for anyone to start building genAI apps with LLMs. 
+
+With Shale Protocol, developers/researchers can create apps and explore the capabilities of open LLMs at no cost.
+
+This page covers how Shale-Serve API can be incorporated with LangChain.
+
+As of June 2023, the API supports Vicuna-13B by default. We are going to support more LLMs such as Falcon-40B in future releases. 
+
+
+## How to
+
+### 1. Find the link to our Discord on https://shaleprotocol.com. Generate an API key through the "Shale Bot" on our Discord. No credit card is required and no free trials. It's a forever free tier with 1K limit per day per API key.
+
+### 2. Use https://shale.live/v1 as OpenAI API drop-in replacement 
+
+For example
+```python
+from langchain.llms import OpenAI
+from langchain import PromptTemplate, LLMChain
+
+import os
+os.environ['OPENAI_API_BASE'] = "https://shale.live/v1"
+os.environ['OPENAI_API_KEY'] = "ENTER YOUR API KEY"
+
+llm = OpenAI()
+
+template = """Question: {question}
+
+# Answer: Let's think step by step."""
+
+prompt = PromptTemplate(template=template, input_variables=["question"])
+
+llm_chain = LLMChain(prompt=prompt, llm=llm)
+
+question = "What NFL team won the Super Bowl in the year Justin Beiber was born?"
+
+llm_chain.run(question)
+
+```