#75 add Greek translation by @zouloumis

resources/messages.properties

@@ -1,5 +1,7 @@
 # Messages in properties format
 # To translate, copy this file to e.g. messages_fr.txt, where "fr" is the language code
+# Delete untranslated lines, include only those which are translated
+
 preferences.language=Language
 preferences.language.needsRestart=You need to restart the app for the language change to take effect
 preferences.language.someIncomplete=Some translations are incomplete
@@ -12,6 +14,7 @@ language.it=Italiano
 language.ku=کوردی
 language.lt=Lietuvių
 language.tr=Türkçe
+language.gr=Ελληνικά
 preferences.csv=CSV
 preferences.csv.separator=CSV separator
 text.progress.ipProgressBar=IP status: