[Issue 19335] std.getopt: make it an error to have options that differ only by case when case insensitive

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=19335

Iain Buclaw <ibuclaw at gdcproject.org> changed:

           What    |Removed                     |Added
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           Priority|P1                          |P3

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