Added Greek language support

lib/src/locale/greek.dart

@@ -0,0 +1,86 @@
+part of duration.locale;
+
+class GreekDurationLocale extends DurationLocale {
+  const GreekDurationLocale();
+
+  @override
+  String year(int amount, [bool abbreviated = true]) {
+    if (abbreviated) {
+      return 'χ';
+    } else {
+      return 'χρόν' + (amount.abs() != 1 ? 'ια' : 'ος');
+    }
+  }
+
+  @override
+  String month(int amount, [bool abbreviated = true]) {
+    if (abbreviated) {
+      return 'μην';
+    } else {
+      return 'μήν' + (amount.abs() != 1 ? 'ες' : 'ας');
+    }
+  }
+
+  @override
+  String week(int amount, [bool abbreviated = true]) {
+    if (abbreviated) {
+      return 'ε';
+    } else {
+      return 'εβδομάδ' + (amount.abs() != 1 ? 'ες' : 'α');
+    }
+  }
+
+  @override
+  String day(int amount, [bool abbreviated = true]) {
+    if (abbreviated) {
+      return 'μ';
+    } else {
+      return 'μέρ' + (amount.abs() != 1 ? 'ες' : 'α');
+    }
+  }
+
+  @override
+  String hour(int amount, [bool abbreviated = true]) {
+    if (abbreviated) {
+      return 'ω';
+    } else {
+      return 'ώρ' + (amount.abs() != 1 ? 'ες' : 'α');
+    }
+  }
+
+  @override
+  String minute(int amount, [bool abbreviated = true]) {
+    if (abbreviated) {
+      return 'λεπ';
+    } else {
+      return 'λεπτ' + (amount.abs() != 1 ? 'ά' : 'ό');
+    }
+  }
+
+  @override
+  String second(int amount, [bool abbreviated = true]) {
+    if (abbreviated) {
+      return 'δ';
+    } else {
+      return 'δευτερόλεπτ' + (amount.abs() != 1 ? 'α' : 'ο');
+    }
+  }
+
+  @override
+  String millisecond(int amount, [bool abbreviated = true]) {
+    if (abbreviated) {
+      return 'χ';
+    } else {
+      return 'χιλιοστ' + (amount.abs() != 1 ? 'ά' : 'ό');
+    }
+  }
+
+  @override
+  String microseconds(int amount, [bool abbreviated = true]) {
+    if (abbreviated) {
+      return 'μ';
+    } else {
+      return 'μικροδευτερόλεπτ' + (amount.abs() != 1 ? 'α' : 'ο');
+    }
+  }
+}

lib/src/locale/locale.dart

@@ -4,6 +4,7 @@ import 'package:duration/duration.dart';
 
 part 'english.dart';
 part 'french.dart';
+part 'greek.dart';
 part 'hebrew.dart';
 part 'polish.dart';
 part 'portuguese_br.dart';
@@ -101,6 +102,9 @@ const EnglishDurationLocale englishLocale = EnglishDurationLocale();
 /// [DurationLocale] for French language
 const FrenchDurationLocale frenchLocale = FrenchDurationLocale();
 
+/// [DurationLocale] for Greek language
+const GreekDurationLocale greekLocale = GreekDurationLocale();
+
 /// [DurationLocale] for Hebrew language
 const HebrewDurationLocale hebrewLocale = HebrewDurationLocale();
 
@@ -174,6 +178,7 @@ const JapaneseDurationLocale japaneseLocale = JapaneseDurationLocale();
 const UkrainianDurationLocale ukrainianLocale = UkrainianDurationLocale();
 
 const _locales = <String, DurationLocale>{
+  'el': greekLocale,
   'en': englishLocale,
   'fr': frenchLocale,
   'he': hebrewLocale,