title: Typescript: is not assignable to type error
body: <p>I am new to using typescript with angular 2. I am using version 1 of angular 2-cli. When compiling, I get this error saying "is not assignable to type Assignment[]". I looked at the data types and it looks okay so far, but I am not sure what the error is exactly. Thanks for your help. </p>
  
  <p><strong>Here is a photo of the error from the console.</strong>
  <a href="https://i.stack.imgur.com/O37l4.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/O37l4.jpg" alt="enter image description here"></a></p>
  
  <p><strong>data.ts file - these are two of the items that appear in the array</strong></p>
  
  <pre><code>export const Assignments: Assignment[] = [
    {
      "a_type": "one",
      "a_title": "Assignment 1",
      "symbol": 1,
      "show": false,
      "tooltip": {
          "left": 82
      },
      "buttonPos":{
          "left": 130
      },
      "printTop": 0,
      "instructions": "Instructions here",
      "due_date": "sept-15.png",
      "percentage": "10.png",
      "taskA": {
          "name": "Option A",
          "a_title": "Task A",
          "information": "Instructions for task A",
          "selectA": true
      }
  }, {
      "a_type": "two",
      "a_title": "Assignment 2",
      "symbol": 2,
      "show": false,
      "sub_a_title": "Assignment Information",
      "tooltip": {
          "left": 200
      },
      "buttonPos":{
          "left": 250
      },
      "printTop": 250,
      "instructions": "Instructions here",
      "due_date": "29.png",
      "percentage": "10.png",
      "taskA": {
        "a_title": "Assignment 2 info",
          "name": "Option A",
          "information": "Instructions for task A",
          "selectA": false
      },
      "taskB": {
        "a_title": "Assignment 2 info",
          "name": "Option B",
          "information": "Instructions for task B",
          "selectB": false
      }
  }
  ]
  </code></pre>
  
  <p><strong>assignment.ts - here's the data types</strong></p>
  
  <pre><code>export class Assignment {
      a_type: string;
      a_title: string;
      symbol: any;
      show: boolean;
      tooltip: any;
      left: number;
      buttonPos:any;
      printTop: number;
      instructions: string;
      due_date: string;
      percentage: string;
      taskA: any;
      name: string;
      information: string;
      selectA: boolean;
      taskB: any;
      selectB: boolean;
    }
  </code></pre>