AK: Make quick_sort() a little more ergonomic

Now it actually defaults to "a < b" comparison, instead of forcing you
to provide a trivial less-than comparator. Also you can pass in any
collection type that has .begin() and .end() and we'll sort it for you.

DevTools/HackStudio/Project.cpp

@@ -60,7 +60,7 @@ struct Project::ProjectTreeNode : public RefCounted<ProjectTreeNode> {
     {
         if (type == Type::File)
             return;
-        quick_sort(children.begin(), children.end(), [](auto& a, auto& b) {
+        quick_sort(children, [](auto& a, auto& b) {
             return a->name < b->name;
         });
         for (auto& child : children)