update news

NEWS.md

@@ -3,12 +3,17 @@ Distributions.jl Release Notes
 
 **Note:** We reached a relatively stable API at version *0.5.0*, and have maintained release notes since then.
 
-Version 0.6
---------------
+Changes from v0.5 to v0.6
+---------------------------
 
-* Add Fréchet Distribution ([#238]).
+* Some bug fixes
 * Add `CategoricalDirectSampler`.
-
+* Add univariate von Mises distribution ([#223])
+* Add Fréchet distribution ([#238])
+* Add noncentral hypergeometric distribution ([#255])
+* More functions for hypergeometric distribution (``support``, ``mode``, ``kurtosis``, ``skewness``, etc) ([#256])
 
 [#238]: https://github.com/JuliaStats/Distributions.jl/pull/238
-
+[#223]: https://github.com/JuliaStats/Distributions.jl/pull/223
+[#255]: https://github.com/JuliaStats/Distributions.jl/pull/255
+[#256]: https://github.com/JuliaStats/Distributions.jl/pull/256