Refactor config and split them in packages (#8351)

This change is related to larger config migration PR
change, this is a first stage change to move our
configs to `cmd/config/` - divided into its subsystems

pkg/env/env.go

@@ -0,0 +1,21 @@
+package env
+
+import "os"
+
+// Get retrieves the value of the environment variable named
+// by the key. If the variable is present in the environment the
+// value (which may be empty) is returned. Otherwise it returns
+// the specified default value.
+func Get(key, defaultValue string) string {
+	if v, ok := os.LookupEnv(key); ok {
+		return v
+	}
+	return defaultValue
+}
+
+// Lookup retrieves the value of the environment variable named
+// by the key. If the variable is present in the environment the
+// value (which may be empty) is returned and the boolean is true.
+// Otherwise the returned value will be empty and the boolean will
+// be false.
+func Lookup(key string) (string, bool) { return os.LookupEnv(key) }