Remove jCenter and replace with mavenCentral

[joshafeinberg]

Closes #103

[chris-mitchell]

LGTM, thanks!

[codecov]

Codecov Report

Merging #104 (281ae13) into main (9bf3b3a) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##               main     #104   +/-   ##
=========================================
  Coverage     50.22%   50.22%           
  Complexity       54       54           
=========================================
  Files            12       12           
  Lines           450      450           
  Branches         95       95           
=========================================
  Hits            226      226           
  Misses          194      194           
  Partials         30       30           

---

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 9bf3b3a...281ae13. Read the comment docs.