chore(deps): update dependency axios to v0.18.0 (#488)

This Pull Request updates dependency [axios](https://github.com/axios/axios) from `v0.15.2` to `v0.18.0`



<details>
<summary>Release Notes</summary>

### [`v0.18.0`](https://github.com/axios/axios/blob/master/CHANGELOG.md#&#8203;0180-Feb-19-2018)
[Compare Source](axios/axios@v0.17.1...v0.18.0)
- Adding support for UNIX Sockets when running with Node.js ([#&#8203;1070](`axios/axios#1070))
- Fixing typings ([#&#8203;1177](`axios/axios#1177)):
    - AxiosRequestConfig.proxy: allows type false
    - AxiosProxyConfig: added auth field
- Adding function signature in AxiosInstance interface so AxiosInstance can be invoked ([#&#8203;1192](`axios/axios#1192), [#&#8203;1254](`axios/axios#1254))
- Allowing maxContentLength to pass through to redirected calls as maxBodyLength in follow-redirects config ([#&#8203;1287](`axios/axios#1287))
- Fixing configuration when using an instance - method can now be set ([#&#8203;1342](`axios/axios#1342))

---

### [`v0.17.1`](https://github.com/axios/axios/blob/master/CHANGELOG.md#&#8203;0171-Nov-11-2017)
[Compare Source](axios/axios@v0.17.0...v0.17.1)
- Fixing issue with web workers ([#&#8203;1160](`axios/axios#1160))
- Allowing overriding transport ([#&#8203;1080](`axios/axios#1080))
- Updating TypeScript typings ([#&#8203;1165](`axios/axios#1165), [#&#8203;1125](`axios/axios#1125), [#&#8203;1131](`axios/axios#1131))

---

### [`v0.17.0`](https://github.com/axios/axios/blob/master/CHANGELOG.md#&#8203;0170-Oct-21-2017)
[Compare Source](axios/axios@v0.16.2...v0.17.0)
- **BREAKING** Fixing issue with `baseURL` and interceptors ([#&#8203;950](`axios/axios#950))
- **BREAKING** Improving handing of duplicate headers ([#&#8203;874](`axios/axios#874))
- Adding support for disabling proxies ([#&#8203;691](`axios/axios#691))
- Updating TypeScript typings with generic type parameters ([#&#8203;1061](`axios/axios#1061))

---

### [`v0.16.2`](https://github.com/axios/axios/blob/master/CHANGELOG.md#&#8203;0162-Jun-3-2017)
[Compare Source](axios/axios@v0.16.1...v0.16.2)
- Fixing issue with including `buffer` in bundle ([#&#8203;887](`axios/axios#887))
- Including underlying request in errors ([#&#8203;830](`axios/axios#830))
- Convert `method` to lowercase ([#&#8203;930](`axios/axios#930))

---

### [`v0.16.1`](https://github.com/axios/axios/blob/master/CHANGELOG.md#&#8203;0161-Apr-8-2017)
[Compare Source](axios/axios@v0.16.0...v0.16.1)
- Improving HTTP adapter to return last request in case of redirects ([#&#8203;828](`axios/axios#828))
- Updating `follow-redirects` dependency ([#&#8203;829](`axios/axios#829))
- Adding support for passing `Buffer` in node ([#&#8203;773](`axios/axios#773))

---

### [`v0.16.0`](https://github.com/axios/axios/blob/master/CHANGELOG.md#&#8203;0160-Mar-31-2017)
[Compare Source](axios/axios@v0.15.3...v0.16.0)
- **BREAKING** Removing `Promise` from axios typings in favor of built-in type declarations ([#&#8203;480](`axios/axios#480))
- Adding `options` shortcut method ([#&#8203;461](`axios/axios#461))
- Fixing issue with using `responseType: 'json'` in browsers incompatible with XHR Level 2 ([#&#8203;654](`axios/axios#654))
- Improving React Native detection ([#&#8203;731](`axios/axios#731))
- Fixing `combineURLs` to support empty `relativeURL` ([#&#8203;581](`axios/axios#581))
- Removing `PROTECTION_PREFIX` support ([#&#8203;561](`axios/axios#561))

---

### [`v0.15.3`](https://github.com/axios/axios/blob/master/CHANGELOG.md#&#8203;0153-Nov-27-2016)
[Compare Source](axios/axios@v0.15.2...v0.15.3)
- Fixing issue with custom instances and global defaults ([#&#8203;443](`axios/axios#443))
- Renaming `axios.d.ts` to `index.d.ts` ([#&#8203;519](`axios/axios#519))
- Adding `get`, `head`, and `delete` to `defaults.headers` ([#&#8203;509](`axios/axios#509))
- Fixing issue with `btoa` and IE ([#&#8203;507](`axios/axios#507))
- Adding support for proxy authentication ([#&#8203;483](`axios/axios#483))
- Improving HTTP adapter to use `http` protocol by default ([#&#8203;493](`axios/axios#493))
- Fixing proxy issues ([#&#8203;491](`axios/axios#491))

---

</details>




---

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package.json

@@ -49,7 +49,7 @@
   "author": "Jim Cummins <jimthedev@gmail.com> (https://github.com/jimthedev)",
   "license": "MIT",
   "devDependencies": {
-    "axios": "0.15.2",
+    "axios": "0.18.0",
     "babel-cli": "6.26.0",
     "babel-core": "6.26.3",
     "babel-preset-es2015": "6.24.1",