move typings dependency to dependencies
move typings dependency to dependencies

with the typings dependency in devDependencies, it will fail to install
when users use  since the postinstall script
uses typings.

flexxis/angular2-jwt,flexxis/angular2-jwt,HaidarZ/ng2-auth,hoalex/angular2-jwt,escardin/angular2-jwt,escardin/angular2-jwt,auth0/angular2-jwt,HaidarZ/ng2-auth,hoalex/angular2-jwt,auth0/angular2-jwt,auth0/angular2-jwt