Update doctrine to the latest version 🚀 (#59)

## The devDependency [doctrine](https://github.com/eslint/doctrine) was updated from `2.1.0` to `3.0.0`.
This version is **not covered** by your **current version range**.

If you don’t accept this pull request, your project will work just like it did before. However, you might be missing out on a bunch of new features, fixes and/or performance improvements from the dependency update.

---

<details>
<summary>Release Notes for v3.0.0</summary>

<ul>
<li><a class="commit-link" href="https://urls.greenkeeper.io/eslint/doctrine/commit/0b5a8c78824798ded2329001723886e8269da08d"><tt>0b5a8c7</tt></a> Breaking: drop support for Node &lt; 6 (<a class="issue-link js-issue-link" data-error-text="Failed to load issue title" data-id="378433675" data-permission-text="Issue title is private" data-url="eslint/doctrine#223" data-hovercard-type="pull_request" data-hovercard-url="/eslint/doctrine/pull/223/hovercard" href="https://urls.greenkeeper.io/eslint/doctrine/pull/223">#223</a>) (Kai Cataldo)</li>
<li><a class="commit-link" href="https://urls.greenkeeper.io/eslint/doctrine/commit/a05e9f270dcb31c12999e1e5b6bac0335d904821"><tt>a05e9f2</tt></a> Upgrade: eslint-release@1.0.0 (<a class="issue-link js-issue-link" data-error-text="Failed to load issue title" data-id="371258798" data-permission-text="Issue title is private" data-url="eslint/doctrine#220" data-hovercard-type="pull_request" data-hovercard-url="/eslint/doctrine/pull/220/hovercard" href="https://urls.greenkeeper.io/eslint/doctrine/pull/220">#220</a>) (Teddy Katz)</li>
<li><a class="commit-link" href="https://urls.greenkeeper.io/eslint/doctrine/commit/36ed02794b7d65339366f77a6f90892eadeee6cf"><tt>36ed027</tt></a> Chore: upgrade coveralls to ^3.0.1 (<a class="issue-link js-issue-link" data-error-text="Failed to load issue title" data-id="325899308" data-permission-text="Issue title is private" data-url="eslint/doctrine#213" data-hovercard-type="pull_request" data-hovercard-url="/eslint/doctrine/pull/213/hovercard" href="https://urls.greenkeeper.io/eslint/doctrine/pull/213">#213</a>) (Teddy Katz)</li>
<li><a class="commit-link" href="https://urls.greenkeeper.io/eslint/doctrine/commit/8667e34a3ecf377d119d1dab4376c8be71fd95bf"><tt>8667e34</tt></a> Upgrade: eslint-release@^0.11.1 (<a class="issue-link js-issue-link" data-error-text="Failed to load issue title" data-id="310208286" data-permission-text="Issue title is private" data-url="eslint/doctrine#210" data-hovercard-type="pull_request" data-hovercard-url="/eslint/doctrine/pull/210/hovercard" href="https://urls.greenkeeper.io/eslint/doctrine/pull/210">#210</a>) (Kevin Partington)</li>
</ul>
</details>

<details>
<summary>Commits</summary>
<p>The new version differs by 6 commits.</p>
<ul>
<li><a href="https://urls.greenkeeper.io/eslint/doctrine/commit/42434ca1f85b264a88afcfd317487a7417e6004b"><code>42434ca</code></a> <code>3.0.0</code></li>
<li><a href="https://urls.greenkeeper.io/eslint/doctrine/commit/9655671fb175decb8f3969f3442aec4fad4922d6"><code>9655671</code></a> <code>Build: changelog update for 3.0.0</code></li>
<li><a href="https://urls.greenkeeper.io/eslint/doctrine/commit/0b5a8c78824798ded2329001723886e8269da08d"><code>0b5a8c7</code></a> <code>Breaking: drop support for Node &lt; 6 (#223)</code></li>
<li><a href="https://urls.greenkeeper.io/eslint/doctrine/commit/a05e9f270dcb31c12999e1e5b6bac0335d904821"><code>a05e9f2</code></a> <code>Upgrade: eslint-release@1.0.0 (#220)</code></li>
<li><a href="https://urls.greenkeeper.io/eslint/doctrine/commit/36ed02794b7d65339366f77a6f90892eadeee6cf"><code>36ed027</code></a> <code>Chore: upgrade coveralls to ^3.0.1 (#213)</code></li>
<li><a href="https://urls.greenkeeper.io/eslint/doctrine/commit/8667e34a3ecf377d119d1dab4376c8be71fd95bf"><code>8667e34</code></a> <code>Upgrade: eslint-release@^0.11.1 (#210)</code></li>
</ul>
<p>See the <a href="https://urls.greenkeeper.io/eslint/doctrine/compare/fdd0004782f218c4362fd928d82ef0e84a8e64d3...42434ca1f85b264a88afcfd317487a7417e6004b">full diff</a></p>
</details>

<details>
  <summary>FAQ and help</summary>

  There is a collection of [frequently asked questions](https://greenkeeper.io/faq.html). If those don’t help, you can always [ask the humans behind Greenkeeper](https://github.com/greenkeeperio/greenkeeper/issues/new).
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package.json

@@ -43,7 +43,7 @@
     "@babel/preset-react": "^7.0.0",
     "@babel/register": "^7.0.0",
     "cross-env": "^5.1.6",
-    "doctrine": "^2.0.0",
+    "doctrine": "^3.0.0",
     "eslint": "^5.3.0",
     "eslint-config-airbnb": "^17.1.0",
     "eslint-plugin-import": "^2.14.0",