BUDAPEST (Reuters) -Hungary will extend a cap on fuel prices for another three months, Prime Minister Viktor Orban said on Saturday, the latest anti-inflation measure announced by his government ahead of an April 3 election. For the first time since he took power in a 2010 election landslide, Orban and his ruling nationalist Fidesz party will face a united front of opposition parties at the polls. Minutes before Orban started his annual state of the nation speech on Saturday, opposition leader Peter Marki-Zay said on Facebook that the six-party alliance had gathered enough signatures to field …