Remove config file migrator (#1045)

* rm migrator consts

* Delete migrator.go

* rm RunMigrations()

core/core.go

@@ -33,8 +33,6 @@ func Start() error {
 	resetDirectories()
 
 	data.PopulateDefaults()
-	// Once a couple versions pass we can remove the old data migrators.
-	data.RunMigrations()
 
 	if err := data.VerifySettings(); err != nil {
 		log.Error(err)