[LyX/master] Improve LaTeX version checking

[Jürgen Spitzmüller]

Am Dienstag, dem 10.01.2023 um 17:28 +0100 schrieb Jean-Marc
Lasgouttes:
> Am I wrong that
> "2015/10/01" >= "2014/06/01"
> ?
> 
> I may be missing something obvious.

Maybe I miss something obvious, but I thought strings can only be
compared for equality (== or !=) not size difference (unless you want
to compare string lengths)

-- 
Jürgen