Update superagent to version 1.7.2 🚀

[greenkeeperio-bot]

Hello :wave:

:rocket::rocket::rocket:

superagent just published its new version 1.7.2, which is not covered by your current version range.

If this pull request passes your tests you can publish your software with the latest version of superagent – otherwise use this branch to work on adaptions and fixes.

Happy fixing and merging :palm_tree:

---

GitHub Release

• Fix case-sensitivity of header fields introduced by a4ddd6a. (Edward J. Jinotti)
• bump extend dependency, as former version did not contain any license information (Lukas Eipert)

---

The new version differs by 6 commits .

• 22a73dd v1.7.2
• bf6574b Merge pull request #869 from leipert/master
• ed0de8f bump extend dependency, as former version did not contain any license information
• 42c18b9 Merge pull request #868 from ejinotti/master
• 32b5d4b Add case-insensitivity tests.
• a1bf6b4 Fix case-sensitivity of header fields introduced by a4ddd6a.

See the full diff.

---

This pull request was created by greenkeeper.io. It keeps your software, up to date, all the time.

_{Tired of seeing this sponsor message? Upgrade to the supporter plan! You'll also get your pull requests faster :zap:}