updated Greek translation

docs/Changelog

@@ -5,8 +5,10 @@ pisg (0.63) - ??
    * Choose locally-installed pisg versions ahead of system-installed pisg
      versions. (thanks, Bruce W. Murphy)
    Christoph:
-   * Updated the Swedish foul1 template (thanks, Torbjörn Svensson).
-   * Updated some German strings (thanks, Igge).
+   * Updated translations:
+     + German (thanks, Igge).
+     + Greek (thanks, Konstantinos Tzanidis)
+     + Swedish (thanks, Torbjörn Svensson).
    * Inhibit warning in _mostreferencednicks when a nick is referenced
      before being used first.
    * Links for users in "These didn't make it to the top" (thanks, Edward

lang.txt

@@ -3553,6 +3553,7 @@ urlstopic = "
 notopic = "Δεν δηλώθηκε κάποιο topic στο κανάλι."
 mostnickstopic = "Χρήστες με τα περισσότερα ψευδώνυμα"
 bylinetopic = "από [:nick] στις [:time]"
+dailyactivitytopic = "Ημερήσια δραστηριότητα (τις τελευταίες [:n] ημέρες)"
 
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