fog/fog — pull request #3039 by fcheung (2014-07-05 10:45:23+00:00)
Title: Support modify subnet attribute for AWS VPC

The only thing modify subnet attribute can modify is the MapPublicIpOnLaunch flag.

I chose to have the option passed be `MapPublicIpOnLaunch` rather than `MapPublicIpOnLaunch.Value` - although that's the parameter name the api actually required it felt a bit over the top so i thought it was ok to handle that for callers of the request