exchange api tester app

[nutmix]

a web front end to support testing the wallet. Only one function, to show price and buy skycoin.
Very simple web interface (e.g. using react)
Check out what the api needs, and allow this to be entered. e.g. it may require you paste in your skycoin address, and it may then show you a BTC address (like OTC).

1. check how api works
2. do a wire frame with the fields required and let me know what it looks like so we can discuss.
3. after discussion, implement.
4. setup travis auto-deploy script to our test server.

[AlexSugak]

working on this