CHANGELOG.txt --> CHANGELOG.md

[jGaboardi]

MANIFEST.in included CHANGELOG.txt, which hasn't existed for quite some time. Updating the current CHANGELOG.md.

[codecov]

Codecov Report

Merging #455 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #455   +/-   ##
=======================================
  Coverage   97.85%   97.85%           
=======================================
  Files           3        3           
  Lines        1120     1120           
  Branches      269      269           
=======================================
  Hits         1096     1096           
  Misses          6        6           
  Partials       18       18

---

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 fd6c5a3...c1aa26b. Read the comment docs.

[jGaboardi]

• improved trouble shooting with reduced timeout
• no single set of unit tests should take longer than 5 minutes