Add tasks for all the new languages

Task/Priority-queue/Sidef/priority-queue.sidef

@@ -0,0 +1,30 @@
+class PriorityQueue {
+    has tasks = []
+
+    method insert (Number priority { _ >= 0 }, task) {
+        for n in range(tasks.len, priority) {
+            tasks[n] = []
+        }
+        tasks[priority].append(task)
+    }
+
+    method get      { tasks.first { !.is_empty } -> shift }
+    method is_empty { tasks.all   {  .is_empty } }
+}
+
+var pq = PriorityQueue()
+
+[
+    [3, 'Clear drains'],
+    [4, 'Feed cat'],
+    [5, 'Make tea'],
+    [9, 'Sleep'],
+    [3, 'Check email'],
+    [1, 'Solve RC tasks'],
+    [9, 'Exercise'],
+    [2, 'Do taxes'],
+].each { |pair|
+    pq.insert(pair...)
+}
+
+say pq.get while !pq.is_empty