[ja] Remove unnecessary translator's note

A public key is public by nature. No need to worry about sending it over email.
[nl] Retranslate chapter08. Remove Babelfishes and clarify text.
Merge pull request #662 from rinopo/patch-1

[ja] Remove unnecessary translator's note
Merge pull request #663 from Cpt-xx/chapter08

[nl] Retranslate chapter08. Remove Babelfishes and clarify text.