ABIDJAN (Reuters) – As darkness falls over Ivory Coast's lagoon-side commercial capital a steady thumping cuts through the tropical night. But where once the thud of heavy weapons set the Abidjan's residents scrambling indoors for cover, tonight it is a reggae bass line that draws them out. Here, little over a year ago, supporters of then-president Laurent Gbagbo and his rival Alassane Ouattara were fighting a brief post-election civil war, the final deadly showdown of a decade-long political crisis. …