removed unnecessary deps

Author: Daniel Winkler

Project.toml

@@ -5,9 +5,7 @@ version = "2.0.1"
 
 [deps]
 CategoricalArrays = "324d7699-5711-5eae-9e2f-1d82baa6b597"
-JSON = "682c06a0-de6a-54ab-a142-c8b1cf79cde6"
 JSON3 = "0f8b85d8-7281-11e9-16c2-39a750bddbf1"
-JSONTables = "b9914132-a727-11e9-1322-f18e41205b0b"
 Mmap = "a63ad114-7e13-5084-954f-fe012c677804"
 OrderedCollections = "bac558e1-5e72-5ebc-8fee-abe8a469f55d"
 StructTypes = "856f2bd8-1eba-4b0a-8007-ebc267875bd4"