Issue #6537: Improved name search for diacritics

[SJuliez]

Fixes #6537
In the unit selector, allows base latin characters to find diacritics. Both "Gött" and "Gott" will find the "Götterdämmerung", "Gun" will find the "Gún" and "Arana" the "Aran~a" (cant even find how to type that)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 29.03%. Comparing base (1d6c24b) to head (3fd3246).
Report is 36 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #6538      +/-   ##
============================================
- Coverage     29.05%   29.03%   -0.02%     
+ Complexity    15160    15158       -2     
============================================
  Files          2835     2836       +1     
  Lines        279129   279296     +167     
  Branches      49214    49237      +23     
============================================
- Hits          81104    81103       -1     
- Misses       192652   192817     +165     
- Partials       5373     5376       +3     

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[pavelbraginskiy]

Accent normalization doesn't cover some letters like ø. I don't know if this is a problem now, but it's possible it could be in the future. A way to solve this would be to add a dependency on ICU4J, which has a bunch of utilities for working with Unicode, including a transliterator that does exactly what we want here.

Example:

var transliterator = Transliterator.getInstance("Latin-ASCII");
System.out.println(transliterator.transliterate("Gøtterdämmerung"));
// Gotterdammerung

Note: the transliterator "Any-Latin; Latin-ASCII" will handle non-Latin scripts but that might be overkill

In general, Unicode is hard, and I think it makes sense to leave figuring it out to the experts.

[RaozSpaz]

Was suggested on Discord to add a request to this for this issue: #6550