update NEWS, README

Author: rschwarz

NEWS.md

@@ -1,5 +1,9 @@
 # News
 
+## v0.9.1
+
+- Add a Julia wrapper for constraint handlers. [109](https://github.com/SCIP-Interfaces/SCIP.jl/pull/109)
+
 ## v0.9.0
 
 - support MOI v0.9 [#126](https://github.com/SCIP-Interfaces/SCIP.jl/pull/126)

README.md

@@ -20,7 +20,8 @@ The goal is to support [JuMP](https://github.com/JuliaOpt/JuMP.jl) (from version
 Currently, we support LP, MIP and QCP problems, as well as some nonlinear constraints, both through `MOI` sets
 (e.g., for second-order cones) as well as for expression graphs (see below).
 
-We still have feature loss in the area of callbacks compared to previous versions.
+It is now possible to implement SCIP constraint handlers in Julia. Other plugin
+types are not yet supported.
 
 ## Getting Started