[Feature]: Add support for creating app using yaml config (#787)

embedchain/yaml/chroma.yaml

@@ -0,0 +1,26 @@
+app:
+  config:
+    id: 'my-app'
+    collection_name: 'my-app'
+
+llm:
+  provider: openai
+  model: 'gpt-3.5-turbo'
+  config:
+    temperature: 0.5
+    max_tokens: 1000
+    top_p: 1
+    stream: false
+
+vectordb:
+  provider: chroma
+  config:
+    collection_name: 'my-app'
+    dir: db
+    allow_reset: true
+
+embedder:
+  provider: openai
+  config:
+    model: 'text-embedding-ada-002'
+    deployment_name: null