Translation updates

resources/langs/nheko_de.ts

resources/langs/nheko_el.ts

resources/langs/nheko_en.qm

resources/langs/nheko_en.ts

resources/langs/nheko_fi.ts

resources/langs/nheko_fr.ts

resources/langs/nheko_ja.ts

resources/langs/nheko_nl.ts

resources/langs/nheko_pl.ts

resources/langs/nheko_ru.ts

resources/langs/nheko_zh_CN.ts

src/Cache.cpp

src/ChatPage.cpp

src/RegisterPage.cpp

src/SSOHandler.cpp

src/timeline/TimelineModel.cpp