[Nimbus SDK] Implement version targeting

[tarikeshaq]

fixes https://mozilla-hub.atlassian.net/browse/SDK-350

ports the desktop implementation of version comparison into the SDK

I still have a couple of todos in there, but otherwise, this should be in a good state. I wrote some docs in versioning.rs that will eventually be published on https://mozilla.github.io/application-services/book/rust-docs/nimbus/index.html

@travis79 feel free to modify this as you see fit - and let me know if there any more clarifications I can add to the brief docs I added (or if anything is confusing)

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[codecov-commenter]

Codecov Report

Merging #4752 (d944319) into main (4adb469) will increase coverage by 0.83%.
The diff coverage is 95.07%.

@@            Coverage Diff             @@
##             main    #4752      +/-   ##
==========================================
+ Coverage   80.53%   81.37%   +0.83%     
==========================================
  Files          48       49       +1     
  Lines        5220     5541     +321     
==========================================
+ Hits         4204     4509     +305     
- Misses       1016     1032      +16     

Impacted Files	Coverage Δ
components/nimbus/src/error.rs	11.76% <0.00%> (-0.74%)	⬇️
components/nimbus/src/lib.rs	86.37% <ø> (ø)
components/nimbus/src/evaluator.rs	98.38% <93.84%> (-0.70%)	⬇️
components/nimbus/src/versioning.rs	96.12% <96.12%> (ø)

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[travis79]

🎉

[travis79]

Looks great! r+