Shares in supermajor Chevron and the biggest U.S. refiners soared in pre-market trade on Monday after U.S. President Donald Trump opened the door to American investment in Venezuela’s oil industry following the capture of Nicolas Maduro. Chevron, which is currently the only U.S. and Western oil firm authorized by the United States to operate in Venezuela, saw its shares jump by 6% in pre-market trade. Chevron, as well as other integrated U.S. oil companies, are set to benefit from the touted opening of Venezuela’s…