Add tasks for all the new languages

Task/Priority-queue/Nim/priority-queue-2.nim

@@ -0,0 +1,18 @@
+import tables
+
+var
+  pq = initTable[int, string]()
+
+proc main() =
+  pq.add(3, "Clear drains")
+  pq.add(4, "Feed cat")
+  pq.add(5, "Make tea")
+  pq.add(1, "Solve RC tasks")
+  pq.add(2, "Tax return")
+
+  for i in countUp(1,5):
+    if pq.hasKey(i):
+      echo i, ": ", pq[i]
+      pq.del(i)
+
+main()