Add compliant event handler as extra, for use in other languages

[biojppm]

No description provided.

[codecov]

Codecov Report

❌ Patch coverage is 99.44196% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 97.50%. Comparing base (9a044c8) to head (9a52890).
⚠️ Report is 50 commits behind head on master.

Files with missing lines	Patch %	Lines
src/c4/yml/parse_engine.def.hpp	85.71%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #536      +/-   ##
==========================================
+ Coverage   97.43%   97.50%   +0.06%     
==========================================
  Files          34       44      +10     
  Lines       11600    12835    +1235     
==========================================
+ Hits        11303    12515    +1212     
- Misses        297      320      +23     

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[coveralls]

Pull Request Test Coverage Report for Build 18081027397

Details

• 982 of 989 (99.29%) changed or added relevant lines in 17 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.3%) to 97.64%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src_extra/c4/yml/extra/ints_to_testsuite.hpp	11	12	91.67%
tools/yaml_events.cpp	196	197	99.49%
src/c4/yml/parse_engine.def.hpp	30	35	85.71%

Totals
Change from base Build 17971675012:	0.3%
Covered Lines:	13031
Relevant Lines:	13346

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💛 - Coveralls