prep for 0.18.4

NEWS.md

@@ -1,6 +1,11 @@
 JuMP release notes
 ==================
 
+Version 0.18.4 (October 8, 2018)
+--------------------------------
+
+   * Fix a bug in model printing on Julia 0.7 and 1.0.
+
 Version 0.18.3 (October 1, 2018)
 ------------------------------
 

README.md

@@ -41,7 +41,7 @@ Our documentation includes an installation guide, quick-start guide, and referen
 
 **Read about the upcoming transition to [MathOptInterface](https://github.com/JuliaOpt/MathOptInterface.jl) (MOI) and breaking changes in JuMP 0.19 [here](https://discourse.julialang.org/t/mathoptinterface-and-upcoming-breaking-changes-in-jump-0-19). The development version of JuMP (`master` branch) supports MOI and is ready for early adopters to test out. Be aware that the development version is alpha quality and is still undergoing breaking changes.**
 
-**Latest Release**: 0.18.3 (`release-0.18` branch)
+**Latest Release**: 0.18.4 (`release-0.18` branch)
   * [Documentation](http://www.juliaopt.org/JuMP.jl/0.18/)
   * [Examples](https://github.com/JuliaOpt/JuMP.jl/tree/release-0.18/examples)
   * Testing status: