refactor: migrate JSON function to new package

We now use it to help read remote docker registries also.

web/web.go

@@ -0,0 +1,18 @@
+package web
+
+import (
+	"encoding/json"
+	"net/http"
+	"time"
+)
+
+// ReadJSON reads JSON and parses it into your chosen interface pointer
+func ReadJSON(url string, target interface{}) error {
+	httpClient := &http.Client{Timeout: 5 * time.Second}
+	res, err := httpClient.Get(url)
+	if err != nil {
+		return err
+	}
+	defer res.Body.Close()
+	return json.NewDecoder(res.Body).Decode(target)
+}