Added Config Trait

[DarkSide666]

ConfigTrait implementation. Mostly useful for using in \atk4\ui\App, but could be used anywhere.

Thanks @gowrav-vishwakarma for initial version of this!

• Docs missing

[codecov]

Codecov Report

Merging #86 into develop will increase coverage by 0.01%.
The diff coverage is 100%.

@@              Coverage Diff              @@
##             develop      #86      +/-   ##
=============================================
+ Coverage      99.82%   99.84%   +0.01%     
- Complexity       253      276      +23     
=============================================
  Files             12       13       +1     
  Lines            584      631      +47     
=============================================
+ Hits             583      630      +47     
  Misses             1        1

Impacted Files	Coverage Δ	Complexity Δ
src/ConfigTrait.php	100% <100%> (ø)	23 <23> (?)

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[romaninsh]

Does it support array in json/ yaml? None in tests. Good addition!