Colorado just added post-traumatic stress disorder (PTSD) to the list of qualifying conditions for the state's medical marijuana program. The Cannabist reports: Gov. John Hickenlooper on Monday signed Senate Bill 17 into law. The bill opens the doors for Colorado residents to receive a doctor’s OK to use medical marijuana in the treatment of PTSD symptoms. It’s the first new qualifying condition added under the state’s medical marijuana law since it was implemented in 2001. The state’s eight other…