update JSON version reqs for package registry

ccoffrin · ccoffrin · commit 4090bc2a9e9a · 2019-12-20T10:56:33.000-07:00
diff --git a/Project.toml b/Project.toml
@@ -17,7 +17,7 @@ SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 Cbc = ">= 0.4"
 InfrastructureModels = "~0.3.1"
 Ipopt = ">= 0.4"
-JSON = ">= 0.18, < 1.0"
+JSON = "~0.18, ~0.19, ~0.20, ~0.21"
 JuMP = "~0.19.1, ~0.20"
 Juniper = ">= 0.4"
 MathOptInterface = "~0.8, ~0.9"
