feature: Add equality comparer to MRUCache, now uses ValueTuple

[glennawatson]

No description provided.

[codecov]

Codecov Report

Merging #344 into master will increase coverage by <.01%.
The diff coverage is 75%.

@@            Coverage Diff             @@
##           master     #344      +/-   ##
==========================================
+ Coverage   70.68%   70.69%   +<.01%     
==========================================
  Files          65       65              
  Lines        3544     3545       +1     
  Branches      316      317       +1     
==========================================
+ Hits         2505     2506       +1     
  Misses        997      997              
  Partials       42       42

Impacted Files	Coverage Δ
src/Splat/MemoizingMRUCache.cs	59.25% <75%> (+0.5%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update a7aa168...d77e0ba. Read the comment docs.