Add tasks for all the new languages

Task/Five-weekends/Nim/five-weekends.nim

@@ -0,0 +1,18 @@
+import times
+
+const LongMonths = {mJan, mMar, mMay, mJul, mAug, mOct, mDec}
+
+var timeinfo = getLocalTime getTime()
+timeinfo.monthday = 1
+
+var sumNone = 0
+for year in 1900..2100:
+  var none = true
+  for month in LongMonths:
+    timeinfo.year = year
+    timeinfo.month = month
+    if getLocalTime(timeInfoToTime timeinfo).weekday == dFri:
+      echo month," ",year
+      none = false
+  if none: inc sumNone
+echo "Years without a 5 weekend month: ",sumNone