Adds ReplaySubject and Publisher.share(replay:)

[jasdev]

h/t to @tcldr for the reference implementation I leaned on and adapted to Shai’s DemandBuffer type. 💯

[codecov]

Codecov Report

Merging #23 into master will increase coverage by 0.19%.
The diff coverage is 97.89%.

@@            Coverage Diff             @@
##           master      #23      +/-   ##
==========================================
+ Coverage   96.94%   97.14%   +0.19%     
==========================================
  Files          34       38       +4     
  Lines        1638     2066     +428     
==========================================
+ Hits         1588     2007     +419     
- Misses         50       59       +9     

Impacted Files	Coverage Δ
Sources/Subjects/ReplaySubject.swift	82.35% <82.35%> (ø)
Sources/Operators/ShareReplay.swift	100.00% <100.00%> (ø)
Tests/ReplaySubjectTests.swift	100.00% <100.00%> (ø)
Tests/ShareReplayTests.swift	100.00% <100.00%> (ø)

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[tcldr]

h/t to @tcldr for the reference implementation I leaned on and adapted to Shai’s Sink type. 💯

Glad it’s been useful! 👍

[freak4pc]

I didn't go over the tests yet, I'll do that later locally,
Most of the notes are just formatting, nothing logic-wise except 1 question

Great work! 👏

[jasdev]

Should be good for another pass over, thanks for the thorough review, Shai. 🙏🏽

[freak4pc]

Second pass, this should be everything I have in mind ;)
Sorry for the lengthy review but this is a big piece of code with 2 very useful features :) Thanks!

[jasdev]

Aaand round-two feedback incorporated. 🤞🏽

Thanks again for the reads over this!

[freak4pc]

Last note!!

[freak4pc]