native nvault_touch(vault, const key, timestamp=-1);
A vault handle returned from nvault_open()
The key to search for
Update an entry's timestamp to this one. Default is -1.
"Touches" an entry in the vault, updating its timestamp.
If timestamp is equal to -1, it will use the current time.
An empty entry is created if one with the given key doesn't exist.
This function has no return value.
On invalid vault handle.