Use github ci

[ViralBShah]

No description provided.

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@47a913b). Click here to learn what that means.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #111   +/-   ##
=========================================
  Coverage          ?   39.74%           
=========================================
  Files             ?       12           
  Lines             ?      478           
  Branches          ?        0           
=========================================
  Hits              ?      190           
  Misses            ?      288           
  Partials          ?        0           

---

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 47a913b...9d8fc93. Read the comment docs.

[nalimilan]

For the record, this PR mistakenly dropped CI on Julia 1.0 without bumping the required version in Project.toml, and later PRs broke pre-1.3 Julia compatibility without anybody noticing. We should be very careful about this. See #138.