Add API route for printer information

src/main.py

@@ -358,6 +358,10 @@ def api_worker_stop():
     worker.stop_worker()
     return jsonify(worker.current_state())
 
+@app.route("/api/printers")
+def api_printers_info():
+    """Returns the current state of every printers"""
+    return jsonify(printers_pool.printers_info())
 
 ## Authentification