Supporters of the legalization of cannabis in Germany are preparing to welcome the entry into force of a new law on Monday with a “smoke-in” at the Brandenburg Gate in the capital Berlin. It would mark the start of “a new era,” the hemp association said. From 11:30 pm (2230 GMT) on Sunday evening, people were being invited to gather at the iconic monument to smoke marijuana in public – but only when the law comes into force. “You can light up at midnight,” the hemp association said. The event has been officially registered with the police as a demonstration. Smaller events are then planned for…