To run:
npm install
jspm install
npm start
I used the following to install bootstrap:
jspm install npm:bootstrap@4.0.0-beta.2 -o "{directories:{lib:'dist'},main:'js/bootstrap.bundle',shim:{'js/bootstrap.bundle':{deps:['jquery','../css/bootstrap.css!']}},dependencies:{},peerDependencies:{jquery:'^3.0.0'}}"