Remove `console` call in App.js

Console shouldn't be called in production code.
Expose "ports" via new app modal form

* Add "ports" form field with a description about random ports
* Bold form errors to differentiate from help text
* Add description about comma-delimitedness of URIs form field

Addresses part of issue #124
Merge pull request #249 from mesosphere/ports-in-new-app-form

Ports in new app form