Add delegator for keys() in arethusaLocalStorage
Add delegator for keys() in arethusaLocalStorage

alpheios-project/arethusa,fbaumgardt/arethusa,fbaumgardt/arethusa,fbaumgardt/arethusa,Masoumeh/arethusa,PonteIneptique/arethusa,PonteIneptique/arethusa,Masoumeh/arethusa,alpheios-project/arethusa,latin-language-toolkit/arethusa,latin-language-toolkit/arethusa,alpheios-project/arethusa