Session exposes a python log

Expose python logger via Session singleton, Session is now inherits singleton metaclass tests to prevent doubling sessions during various testing operations

Closes #4 (closed)

model_server/base/api.py

@@ -62,6 +62,10 @@ def restart_session(root: str = None) -> dict:
     session.restart(root=root)
     return session.describe_loaded_models()
 
+@app.get('/session/logs')
+def list_session_log() -> list:
+    return session.get_log_data()
+
 @app.get('/models')
 def list_active_models():
     return session.describe_loaded_models()