News and compat annotation for #29259

(merge(::NamedTuple...) with more than 2 arguments).

Author: fredrikekre

NEWS.md

@@ -72,6 +72,7 @@ Standard library changes
   * `Symmetric` and `Hermitian` matrices now preserve the wrapper when scaled with a number ([#29469]).
   * New `edit(m::Module)` method which opens the main source file for module `m` ([#29636]).
   * `Base.@kwdef` can now be used for parametric structs, and for structs with supertypes ([#29316]).
+  * `merge(::NamedTuple, ::NamedTuple...)` can now be used with more than 2 `NamedTuple`s ([#29259]).
 
 Compiler/Runtime improvements
 -----------------------------

base/namedtuple.jl

@@ -223,6 +223,10 @@ contains that field. Fields present in only the rightmost named tuple of a pair
 A fallback is implemented for when only a single named tuple is supplied,
 with signature `merge(a::NamedTuple)`.
 
+!!! compat "Julia 1.1"
+    Merging 3 or more `NamedTuple` requires at least Julia 1.1.
+
+# Examples
 ```jldoctest
 julia> merge((a=1, b=2, c=3), (b=4, d=5))
 (a = 1, b = 4, c = 3, d = 5)