Use remote ip for peer ip

[Gladear]

Fixes #34.

Use the conn :remote_ip instead of data gotten through Plug.Conn.get_peer_data/1.
This allows to take into account proxies, whilst keeping the remote peer ip as default.

Take the opportunity to replace use Plug.Test by imports.

[maennchen]

Thanks @Gladear ❤️

[coveralls]

Pull Request Test Coverage Report for Build 548d9f9922a61a27c01cd5474107124fd8784946-PR-35

Details

• 3 of 3 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.04%) to 93.96%

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Totals
Change from base Build f1acac5c77ce8d44fd099be86bc1a7de70c22ba8:	-0.04%
Covered Lines:	140
Relevant Lines:	149

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 548d9f9922a61a27c01cd5474107124fd8784946-PR-35

Details

• 3 of 3 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.04%) to 93.96%

---

Totals
Change from base Build f1acac5c77ce8d44fd099be86bc1a7de70c22ba8:	-0.04%
Covered Lines:	140
Relevant Lines:	149

---

💛 - Coveralls