unable to define no timeout

[benjdv]

When setting timeout of different functions to negative value (ie no timeout) - (example query(sql, timeout=10)) - it produce an error :
ValueError: Attempted to set connect timeout to -1, but the timeout cannot be set to a value less than or equal to 0.
But DRILL documentation precise that
timeout | <integer> | Query timeout in seconds; less than zero means no timeout.

So it will be useful to let this possibility for the user