Add Utils::filtered as a wrapper around std::copy_if

Change-Id: I4a189581a4a7f42f880c47b91372d7e96d50655e
Reviewed-by: Daniel Teske <daniel.teske@theqtcompany.com>

src/libs/utils/algorithm.h

@@ -337,6 +337,18 @@ auto transform(const SC &container, R (S::*p)() const)
             >::call(container, p);
 }
 
+//////////////////
+// filtered
+/////////////////
+template<typename C, typename F>
+C filtered(const C &container, F predicate)
+{
+  C out;
+  std::copy_if(container.begin(), container.end(),
+               inserter(out), predicate);
+  return out;
+}
+
 //////////////////
 // sort
 /////////////////