add generics for spected
add generics for spected

dsebastien/DefinitelyTyped,borisyankov/DefinitelyTyped,markogresak/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped,mcliment/DefinitelyTyped,dsebastien/DefinitelyTyped,georgemarshall/DefinitelyTyped,borisyankov/DefinitelyTyped,georgemarshall/DefinitelyTyped