CI-487: publish stag artifacts and doc to MavenCentral

[MathiasGr]

Ticket

Required for Vimeans only
CI-487

Ticket Summary

publish stag artifacts and doc to MavenCentral

Implementation Summary

Based on the work done for vimeo-networking:

• Fixed Javadoc errors
• Updated Fastlane config
• Updated build.gradle to add the proper pom.xml to stag-library and stag-library-compiler to conform to Metadata needed by Maven central and bintray.
• Bumped version to 2.3.1

[codecov-io]

Codecov Report

Merging #118 into master will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #118   +/-   ##
=========================================
  Coverage     34.64%   34.64%           
  Complexity      167      167           
=========================================
  Files            89       89           
  Lines          2263     2263           
  Branches        343      343           
=========================================
  Hits            784      784           
  Misses         1359     1359           
  Partials        120      120

Impacted Files	Coverage Δ	Complexity Δ
...java/com/vimeo/stag/processor/utils/TypeUtils.java	61.9% <ø> (ø)	59 <0> (ø)	⬇️
...-library/src/main/java/com/vimeo/stag/UseStag.java	0% <ø> (ø)	0 <0> (ø)	⬇️

---

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 4118871...f6f46c5. Read the comment docs.

[anthonycr]

Looks great, just one comment. Can you update the CHANGELOG.md file with information about the release and also update the README.md to point to 2.3.1 instead of 2.3.0?

[anthonycr]

Looks great!