shellcheck fixes; make xdg-mime DASH-compatible
I ran shellcheck on all xdg-* scripts and fixed the low-hanging fruits. Most importantly, I replaced == with = in xdg-mime so that it can be run with dash(1).
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I ran shellcheck on all xdg-* scripts and fixed the low-hanging fruits. Most importantly, I replaced == with = in xdg-mime so that it can be run with dash(1).