A United Launch Alliance Atlas V rocket with Boeing’s CST-100 Starliner spacecraft aboard is rolled out to the launchpad on May 4 ahead of its first crewed launch attempt in Cape Canaveral, Florida. Joel Kowsky/NASAMake no mistake: Today’s launch is a massive deal for Boeing.The company’s airplane woes are one thing, but Starliner has had its own issues.The spacecraft was developed under NASA’s Commercial Crew Program, which got rolling in 2014.That’s when the space agency awarded Boeing and SpaceX contracts to develop spacecraft capable of getting astronauts to the International Space…