Add codesandbox example to the project folder

[halitogunc]

codesandbox is a great online code editor which makes it easier to code and share, but it's not a bad idea to make these files accessible in our own repository.

[codecov[bot]]

Codecov Report

Merging #10 into master will not change coverage. The diff coverage is n/a.

@@          Coverage Diff          @@
##           master    #10   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files           2      2           
  Lines          23     23           
  Branches        2      2           
=====================================
  Hits           23     23

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update e2ad406...50e57de. Read the comment docs.