Add gitignore for venv, datasets, model

.gitignore

@@ -8,6 +8,9 @@ __pycache__/
 
 # Distribution / packaging
 .Python
+/model
+/datasets
+/venv
 /get-pip.py
 build/
 develop-eggs/
@@ -123,8 +126,7 @@ celerybeat.pid
 *.sage.py
 
 # Environments
-Server/.env
-Client/.env
+.env
 .venv
 env/
 venv/