community[major], core[patch], langchain[patch], experimental[patch]: Create langchain-community (#14463)

Moved the following modules to new package langchain-community in a backwards compatible fashion:

```
mv langchain/langchain/adapters community/langchain_community
mv langchain/langchain/callbacks community/langchain_community/callbacks
mv langchain/langchain/chat_loaders community/langchain_community
mv langchain/langchain/chat_models community/langchain_community
mv langchain/langchain/document_loaders community/langchain_community
mv langchain/langchain/docstore community/langchain_community
mv langchain/langchain/document_transformers community/langchain_community
mv langchain/langchain/embeddings community/langchain_community
mv langchain/langchain/graphs community/langchain_community
mv langchain/langchain/llms community/langchain_community
mv langchain/langchain/memory/chat_message_histories community/langchain_community
mv langchain/langchain/retrievers community/langchain_community
mv langchain/langchain/storage community/langchain_community
mv langchain/langchain/tools community/langchain_community
mv langchain/langchain/utilities community/langchain_community
mv langchain/langchain/vectorstores community/langchain_community
mv langchain/langchain/agents/agent_toolkits community/langchain_community
mv langchain/langchain/cache.py community/langchain_community
mv langchain/langchain/adapters community/langchain_community
mv langchain/langchain/callbacks community/langchain_community/callbacks
mv langchain/langchain/chat_loaders community/langchain_community
mv langchain/langchain/chat_models community/langchain_community
mv langchain/langchain/document_loaders community/langchain_community
mv langchain/langchain/docstore community/langchain_community
mv langchain/langchain/document_transformers community/langchain_community
mv langchain/langchain/embeddings community/langchain_community
mv langchain/langchain/graphs community/langchain_community
mv langchain/langchain/llms community/langchain_community
mv langchain/langchain/memory/chat_message_histories community/langchain_community
mv langchain/langchain/retrievers community/langchain_community
mv langchain/langchain/storage community/langchain_community
mv langchain/langchain/tools community/langchain_community
mv langchain/langchain/utilities community/langchain_community
mv langchain/langchain/vectorstores community/langchain_community
mv langchain/langchain/agents/agent_toolkits community/langchain_community
mv langchain/langchain/cache.py community/langchain_community
```

Moved the following to core
```
mv langchain/langchain/utils/json_schema.py core/langchain_core/utils
mv langchain/langchain/utils/html.py core/langchain_core/utils
mv langchain/langchain/utils/strings.py core/langchain_core/utils
cat langchain/langchain/utils/env.py >> core/langchain_core/utils/env.py
rm langchain/langchain/utils/env.py
```

See .scripts/community_split/script_integrations.sh for all changes

libs/community/tests/integration_tests/llms/test_together.py

@@ -0,0 +1,39 @@
+"""Test Together API wrapper.
+
+In order to run this test, you need to have an Together api key.
+You can get it by registering for free at https://api.together.xyz/.
+A test key can be found at https://api.together.xyz/settings/api-keys
+
+You'll then need to set TOGETHER_API_KEY environment variable to your api key.
+"""
+import pytest as pytest
+
+from langchain_community.llms import Together
+
+
+def test_together_call() -> None:
+    """Test simple call to together."""
+    llm = Together(
+        model="togethercomputer/RedPajama-INCITE-7B-Base",
+        temperature=0.2,
+        max_tokens=250,
+    )
+    output = llm("Say foo:")
+
+    assert llm._llm_type == "together"
+    assert isinstance(output, str)
+
+
+async def test_together_acall() -> None:
+    """Test simple call to together."""
+    llm = Together(
+        model="togethercomputer/RedPajama-INCITE-7B-Base",
+        temperature=0.2,
+        max_tokens=250,
+    )
+    output = await llm.agenerate(["Say foo:"], stop=["bar"])
+
+    assert llm._llm_type == "together"
+    output_text = output.generations[0][0].text
+    assert isinstance(output_text, str)
+    assert output_text.count("bar") <= 1