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](`https://github.com/axios/axios/pull/1070`))
- Fixing typings ([#&#8203;1177](`https://github.com/axios/axios/pull/1177`)):
    - AxiosRequestConfig.proxy: allows type false
    - AxiosProxyConfig: added auth field
- Adding function signature in AxiosInstance interface so AxiosInstance can be invoked ([#&#8203;1192](`https://github.com/axios/axios/pull/1192`), [#&#8203;1254](`https://github.com/axios/axios/pull/1254`))
- Allowing maxContentLength to pass through to redirected calls as maxBodyLength in follow-redirects config ([#&#8203;1287](`https://github.com/axios/axios/pull/1287`))
- Fixing configuration when using an instance - method can now be set ([#&#8203;1342](`https://github.com/axios/axios/pull/1342`))

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### [`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](`https://github.com/axios/axios/pull/1160`))
- Allowing overriding transport ([#&#8203;1080](`https://github.com/axios/axios/pull/1080`))
- Updating TypeScript typings ([#&#8203;1165](`https://github.com/axios/axios/pull/1165`), [#&#8203;1125](`https://github.com/axios/axios/pull/1125`), [#&#8203;1131](`https://github.com/axios/axios/pull/1131`))

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### [`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](`https://github.com/axios/axios/pull/950`))
- **BREAKING** Improving handing of duplicate headers ([#&#8203;874](`https://github.com/axios/axios/pull/874`))
- Adding support for disabling proxies ([#&#8203;691](`https://github.com/axios/axios/pull/691`))
- Updating TypeScript typings with generic type parameters ([#&#8203;1061](`https://github.com/axios/axios/pull/1061`))

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### [`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](`https://github.com/axios/axios/pull/887`))
- Including underlying request in errors ([#&#8203;830](`https://github.com/axios/axios/pull/830`))
- Convert `method` to lowercase ([#&#8203;930](`https://github.com/axios/axios/pull/930`))

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### [`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](`https://github.com/axios/axios/pull/828`))
- Updating `follow-redirects` dependency ([#&#8203;829](`https://github.com/axios/axios/pull/829`))
- Adding support for passing `Buffer` in node ([#&#8203;773](`https://github.com/axios/axios/pull/773`))

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### [`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](`https://github.com/axios/axios/issues/480`))
- Adding `options` shortcut method ([#&#8203;461](`https://github.com/axios/axios/pull/461`))
- Fixing issue with using `responseType: 'json'` in browsers incompatible with XHR Level 2 ([#&#8203;654](`https://github.com/axios/axios/pull/654`))
- Improving React Native detection ([#&#8203;731](`https://github.com/axios/axios/pull/731`))
- Fixing `combineURLs` to support empty `relativeURL` ([#&#8203;581](`https://github.com/axios/axios/pull/581`))
- Removing `PROTECTION_PREFIX` support ([#&#8203;561](`https://github.com/axios/axios/pull/561`))

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### [`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](`https://github.com/axios/axios/issues/443`))
- Renaming `axios.d.ts` to `index.d.ts` ([#&#8203;519](`https://github.com/axios/axios/issues/519`))
- Adding `get`, `head`, and `delete` to `defaults.headers` ([#&#8203;509](`https://github.com/axios/axios/issues/509`))
- Fixing issue with `btoa` and IE ([#&#8203;507](`https://github.com/axios/axios/issues/507`))
- Adding support for proxy authentication ([#&#8203;483](`https://github.com/axios/axios/pull/483`))
- Improving HTTP adapter to use `http` protocol by default ([#&#8203;493](`https://github.com/axios/axios/pull/493`))
- Fixing proxy issues ([#&#8203;491](`https://github.com/axios/axios/pull/491`))

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</details>




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