feat(box2d): add a minimal box2d system

[Milerius]

No description provided.

[Milerius]

related to #59

[codecov]

Codecov Report

Merging #71 into master will increase coverage by 0.14%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #71      +/-   ##
==========================================
+ Coverage   96.15%   96.29%   +0.14%     
==========================================
  Files          13       15       +2     
  Lines         182      189       +7     
==========================================
+ Hits          175      182       +7     
  Misses          7        7

Impacted Files	Coverage Δ
.../antara/gaming/box2d/antara.box2d.system.tests.cpp	100% <100%> (ø)
modules/box2d/antara/gaming/box2d/box2d.system.hpp	100% <100%> (ø)

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