README: Fix bad anchor link in ToC + cleanup
README: Fix bad anchor link in ToC + cleanup

leopardpan/SwiftGen,ldiqual/SwiftGen,Nick11/SwiftGen,hoanganh6491/SwiftGen,Nick11/SwiftGen,esttorhe/SwiftGen,alessandrostone/SwiftGen,hoanganh6491/SwiftGen,mackoj/SwiftGen,alessandrostone/SwiftGen,leopardpan/SwiftGen,mackoj/SwiftGen,esttorhe/SwiftGen,ldiqual/SwiftGen