l10n: fixed typos of mismatched constant strings

l10n: fixed typos of mismatched constant strings

Andrei pointed out a typo in the Swedish translation, where a config
variable name had been copied incorrectly.

By introducing typo detection function in "git-po-helper", more typos
were found. All easy-to-fix typos were fixed in this commit.

Reported-by: Andrei Rybak <rybak.a.v@gmail.com>
Signed-off-by: Peter Krefting <peter@softwolves.pp.se>
Signed-off-by: Jiang Xin <worldhello.net@gmail.com>