Prep for Arduino IDE Release of Cpp-Client

[sleepdefic1t]

For Cpp-Client to be released in the Arduino IDE, the following must be done:

1. Create "arduino" branch.
2. Merge https://github.com/sleepdefic1t/cpp-client/tree/arduino to the "arduino" branch.
3. Tag/Release 1.2.0-arduino targeting the "arduino" branch (*first).
4. Tag/Release 1.2.0 targeting Master (*second).

@faustbrian @kristjank @supaiku0
At this time, I need an "arduino" branch.
After my PR is merged to the "arduino" branch, we can proceed with release/tagging.

[faustbrian]

https://github.com/ArkEcosystem/cpp-client/tree/arduino

Let me know when you made the changes needed so I tag the arduino release.

[sleepdefic1t]

@faustbrian #81

[faustbrian]

https://github.com/ArkEcosystem/cpp-client/releases/tag/1.2.0-arduino