No, you have to do it manually. The easiest way to kill the pilot light is to turn off the gas supply valve to the water heater (or furnace, but I'll assume water heater). First turn the control knob on the water heater to off, then find the gas supply line, usually a metal pipe. There will be a valve in that line close to the appliance, usually turning 90 degrees clockwise (you might need to use pliers) will shut it off and the pilot light will go out.
To re-light, take off the cover plate at the bottom of the water heater and make sure you can get a match or a long fireplace butane lighter to reach the burner where the gas tubes go. Turn the supply valve the opposite way to open the gas line, then turn the control knob to the "pilot" position, light a match or the lighter, put it by the gas tubes, and hold down the lighting button by the control knob. The pilot light should start burning, but keep holding the button down for another 30 seconds or so. When you release the button the pilot light should stay on. Usually there are instructions on a label near the control knob for this. Then you can turn the control knob back to the heating position you want and it will fire up.
If you smell gas strongly before the pilot light is lit, turn off the gas supply line and call the gas company.
Justin