prep for v0.18.4 bug fix release

Author: ccoffrin

CHANGELOG.md

@@ -2,6 +2,9 @@ PowerModels.jl Change Log
 =========================
 
 ### Staged
+- nothing
+
+### v0.18.4
 - Improved support for PWL costs with on/off generators
 - Added support for two-terminal HVDC lines to PSSE export (#754)
 - Improved formulation of `relaxation_sin_on_off` constraint (#786)

Project.toml

@@ -2,7 +2,7 @@ name = "PowerModels"
 uuid = "c36e90e8-916a-50a6-bd94-075b64ef4655"
 authors = ["Carleton Coffrin"]
 repo = "https://github.com/lanl-ansi/PowerModels.jl"
-version = "0.18.3"
+version = "0.18.4"
 
 [deps]
 InfrastructureModels = "2030c09a-7f63-5d83-885d-db604e0e9cc0"