Add tasks for all the new languages

Task/Sorting-algorithms-Quicksort/Eero/sorting-algorithms-quicksort-1.eero

@@ -0,0 +1,36 @@
+#import <Foundation/Foundation.h>
+
+void quicksortInPlace(MutableArray array, const long first, const long last)
+  if first >= last
+    return
+  Value pivot = array[(first + last) / 2]
+  left := first
+  right := last
+  while left <= right
+    while array[left] < pivot
+      left++
+    while array[right] > pivot
+      right--
+    if left <= right
+      array.exchangeObjectAtIndex: left++, withObjectAtIndex: right--
+
+  quicksortInPlace(array, first, right)
+  quicksortInPlace(array, left, last)
+
+Array quicksort(Array unsorted)
+  a := []
+  a.addObjectsFromArray: unsorted
+  quicksortInPlace(a, 0, a.count - 1)
+  return a
+
+
+int main(int argc, const char * argv[])
+  autoreleasepool
+    a := [1, 3, 5, 7, 9, 8, 6, 4, 2]
+    Log( 'Unsorted: %@', a)
+    Log( 'Sorted: %@', quicksort(a) )
+    b := ['Emil', 'Peg', 'Helen', 'Juergen', 'David', 'Rick', 'Barb', 'Mike', 'Tom']
+    Log( 'Unsorted: %@', b)
+    Log( 'Sorted: %@', quicksort(b) )
+
+  return 0

Task/Sorting-algorithms-Quicksort/Eero/sorting-algorithms-quicksort-2.eero

@@ -0,0 +1,33 @@
+#import <Foundation/Foundation.h>
+
+implementation Array (Quicksort)
+
+  plus: Array array, return Array =
+    self.arrayByAddingObjectsFromArray: array
+
+  filter: BOOL (^)(id) predicate, return Array
+    array := []
+    for id item in self
+      if predicate(item)
+        array.addObject: item
+    return array.copy
+
+  quicksort, return Array = self
+    if self.count > 1
+      id x = self[self.count / 2]
+      lesser := self.filter: (id y | return y < x)
+      greater := self.filter: (id y | return y > x)
+      return lesser.quicksort + [x] + greater.quicksort
+
+end
+
+int main()
+  autoreleasepool
+    a := [1, 3, 5, 7, 9, 8, 6, 4, 2]
+    Log( 'Unsorted: %@', a)
+    Log( 'Sorted: %@', a.quicksort )
+    b := ['Emil', 'Peg', 'Helen', 'Juergen', 'David', 'Rick', 'Barb', 'Mike', 'Tom']
+    Log( 'Unsorted: %@', b)
+    Log( 'Sorted: %@', b.quicksort )
+
+  return 0