Add std::initializer_list to the following containers:

* deque
* map
* multimap
* set
* multiset
* list
* slist

Tested on clant and g++

test/deque_test.cpp

@@ -341,6 +341,36 @@ int test_cont_variants()
    return 0;
 }
 
+bool test_support_for_initialization_list()
+{
+#if !defined(BOOST_NO_CXX11_HDR_INITIALIZER_LIST)
+   const std::initializer_list<int> il = {1, 10, 11};
+   const deque<int> expectedDeque(il.begin(), il.end());
+
+   const deque<int> testConstructor = il;
+   if(testConstructor != expectedDeque)
+      return false;
+
+   deque<int> testAssignmentOperator = {11, 12, 23};
+   testAssignmentOperator = il;
+   if(testConstructor != expectedDeque)
+      return false;
+
+   deque<int> testAssignmentMethod = {11, 12, 23};
+   testAssignmentMethod.assign(il);
+   if(testConstructor != expectedDeque)
+      return false;
+
+   deque<int> testInsertMethod = {11};
+   testInsertMethod.insert(testInsertMethod.cbegin(), {12, 23});
+   if(testConstructor != expectedDeque)
+      return false;
+
+   return true;
+#endif
+   return true;
+
+}
 
 int main ()
 {
@@ -396,6 +426,9 @@ int main ()
       return 1;
    }
 
+   if(!test_support_for_initialization_list())
+      return 1;
+
    ////////////////////////////////////
    //    Emplace testing
    ////////////////////////////////////