title: Import interface in Angular 2
body: <p>In a Meteor app that uses Angular 2, I want to create a custom data type, something like this:</p>
  
  <pre><code>interface MyCustomType {
    index: number;
    value: string;
  }
  </code></pre>
  
  <p>I then want to use this custom type in multiple files. I've tried creating a separate file named "mycustom.type.ts", with the following content:</p>
  
  <pre><code>export interface MyCustomType {
    index: number;
    value: string;
  }
  </code></pre>
  
  <p>I then attempt to import this type so that it can be used in another file:</p>
  
  <pre><code>import MyCustomType from "./mycustom.type"
  </code></pre>
  
  <p>However, Atom reports the following error:</p>
  
  <pre><code>TS Error File '/.../mycustom.type.ts' is not a module ...
  </code></pre>
  
  <p>How should I be declaring and importing types, so that they can be used in multiple places?</p>