feat: add support for Elastcisearch as vector data source (#402)

docs/advanced/vector_database.mdx

@@ -0,0 +1,34 @@
+---
+title: '💾 Vector Database'
+---
+
+We support `Chroma` and `Elasticsearch` as two vector database. 
+`Chroma` is used as a default database.
+
+### Elasticsearch
+In order to use `Elasticsearch` as vector database we need to use App type `CustomApp`. 
+```python
+import os
+from embedchain import CustomApp
+from embedchain.config import CustomAppConfig, ElasticsearchDBConfig
+from embedchain.models import Providers, EmbeddingFunctions, VectorDatabases
+
+os.environ["OPENAI_API_KEY"] = 'OPENAI_API_KEY'
+
+es_config = ElasticsearchDBConfig(
+	# elasticsearch url or list of nodes url with different hosts and ports.
+	es_url='http://localhost:9200',
+	# pass named parameters supported by Python Elasticsearch client
+	ca_certs="/path/to/http_ca.crt",
+	basic_auth=("username", "password")
+)
+config = CustomAppConfig(
+	embedding_fn=EmbeddingFunctions.OPENAI, 
+	provider=Providers.OPENAI, 
+	db_type=VectorDatabases.ELASTICSEARCH, 
+	es_config=es_config,
+)
+es_app = CustomApp(config)
+```
+- Set `db_type=VectorDatabases.ELASTICSEARCH` and `es_config=ElasticsearchDBConfig(es_url='')` in `CustomAppConfig`.
+- `ElasticsearchDBConfig` accepts `es_url` as elasticsearch url or as list of nodes url with different hosts and ports. Additionally we can pass named paramaters supported by Python Elasticsearch client.

docs/mint.json

@@ -32,7 +32,7 @@
     },
     {
       "group": "Advanced",
-      "pages": ["advanced/app_types", "advanced/interface_types", "advanced/adding_data","advanced/data_types", "advanced/query_configuration", "advanced/configuration", "advanced/testing", "advanced/showcase"]
+      "pages": ["advanced/app_types", "advanced/interface_types", "advanced/adding_data","advanced/data_types", "advanced/query_configuration", "advanced/configuration", "advanced/testing", "advanced/vector_database", "advanced/showcase"]
     },
     {
       "group": "Examples",