update NEWS and FAQ entry on nothingness

NEWS.md

@@ -7,11 +7,30 @@ New language features
   * Unicode version 7 is now supported for identifiers etcetera ([#7917]).
 
   * Type parameters now permit any arbitrary `isbits` type, not just
-    `Int` and `Bool` ([#6081]). 
+    `Int` and `Bool` ([#6081]).
+
+  * Keyword argument names can be computed, using syntax such as `f(; (name, val))` ([#7704]).
+
+  * (TODO pending final syntax) staged functions ([#7311]).
+
+Language changes
+----------------
+
+  * `None` is deprecated; use `Union()` instead ([#8423]).
+
+  * `Nothing` (the type of `nothing`) is renamed to `Void` ([#8423]).
 
 Library improvements
 --------------------
 
+  * `convert` now checks for overflow when truncating integers or converting between
+    signed and unsigned ([#5413]).
+
+  * Arithmetic is type-preserving for more types; e.g. `(x::Int8) + (y::Int8)` now
+    yields an `Int8` ([#3759]).
+
+  * Reductions (e.g. `reduce`, `sum`) widen small types (integers smaller than `Int`, and `Float16`).
+
   * New `Dates` module for calendar dates and other time-interval calculations ([#7654]).
 
   * Added generic Cholesky factorization, and the Cholesky factorization is now parametrized on the matrix type ([#7236]).
@@ -34,6 +53,8 @@ Library improvements
     to provide uniform cross-platform behavior and up-to-date, locale-independent support
     for Unicode standards ([#5939]).
 
+  * New `Nullable` type for missing data ([#8152]).
+
 
 Julia v0.3.0 Release Notes
 ==========================
@@ -961,3 +982,9 @@ Too numerous to mention.
 [#7992]: https://github.com/JuliaLang/julia/issues/7992
 [#8011]: https://github.com/JuliaLang/julia/issues/8011
 [#8089]: https://github.com/JuliaLang/julia/issues/8089
+[#7704]: https://github.com/JuliaLang/julia/issues/7704
+[#5413]: https://github.com/JuliaLang/julia/issues/5413
+[#3759]: https://github.com/JuliaLang/julia/issues/3759
+[#7311]: https://github.com/JuliaLang/julia/issues/7311
+[#8423]: https://github.com/JuliaLang/julia/issues/8423
+[#8152]: https://github.com/JuliaLang/julia/pull/8152

doc/manual/faq.rst

@@ -697,22 +697,24 @@ situation can be detected using the ``isdefined`` function.
 
 Some functions are used only for their side effects, and do not need to
 return a value. In these cases, the convention is to return the value
-``nothing``, which is just a singleton object of type ``Nothing``. This
+``nothing``, which is just a singleton object of type ``Void``. This
 is an ordinary type with no fields; there is nothing special about it
 except for this convention, and that the REPL does not print anything
 for it. Some language constructs that would not otherwise have a value
 also yield ``nothing``, for example ``if false; end``.
 
-Note that ``Nothing`` (uppercase) is the type of ``nothing``, and should
-only be used in a context where a type is required (e.g. a declaration).
-
-You may occasionally see ``None``, which is quite different. It is the
-empty (or "bottom") type, a type with no values and no subtypes (except
-itself). You will generally not need to use this type.
+For situations where a value exists only sometimes (for example, missing
+statistical data), it is best to use the ``Nullable{T}`` type, which allows
+specifying the type of a missing value.
 
 The empty tuple (``()``) is another form of nothingness. But, it should not
 really be thought of as nothing but rather a tuple of zero values.
 
+In code written for Julia prior to version 0.4 you may occasionally see ``None``,
+which is quite different. It is the empty (or "bottom") type, a type with no values
+and no subtypes (except itself). This is now written as ``Union()`` (an empty union
+type). You will generally not need to use this type.
+
 Julia Releases
 ----------------