Language corr. (2)

l. 207: "Benutzerkontos", I've added the Genitive-suffix /-s/
l. 406, spelling of "Benutzer-Online-Liste"
l. 439/448/457/466: You've switched from third person to informal "you", thus I changed that. However, I'm note sure wehether the informal version is the standard text within social networks. If so, re-write my changes. Moreover, I've a added a comma because of grammatical rules (zweo verbs).
l. 557: I've deleted "aktuelles" as birthday implies one's actutal birthday and not e.g. the one two years ago or the one in the future.