Update NEWS.md for Libdl.{dlopen,dlsym} changes

NEWS.md

@@ -11,11 +11,21 @@ Refer to the [Release Notes for
 v0.7](https://github.com/JuliaLang/julia/blob/master/HISTORY.md) for a
 detailed list of changes from Julia v0.6.
 
+Standard Library Changes
+------------------------
+
+* The `Libdl` module's methods `dlopen_e()` and `dlsym_e()` have been
+  updated to return `nothing` as the indicator of a nonexistent symbol
+  or library.  Additionally, the `dlopen()` and `dlsym()` methods have
+  gained a `throw_error` keyword argument, to replace usages such as
+  `dlsym_e(args...)` with `dlsym(args...; throw_error=false)`. ([#28888])
+
 Deprecated or removed
 ---------------------
 
-The old package manager (now called `OldPkg`) has been moved to a
-separate repository at https://github.com/JuliaArchive/OldPkg.jl ([#27930])
+* The old package manager (now called `OldPkg`) has been moved to a
+  separate repository at https://github.com/JuliaArchive/OldPkg.jl ([#27930])
 
 <!--- generated by NEWS-update.jl: -->
 [#27930]: https://github.com/JuliaLang/julia/issues/27930
+[#28888]: https://github.com/JuliaLang/julia/issues/28888