README: clarify elevated installation
@@ -124,6 +124,11 @@ To install all available utilities:
$ make install
```
+To install using `sudo` switch `-E` must be used:
+```bash
+$ sudo -E make install
+```
+
To install all but a few of the available utilities:
```bash
$ make SKIP_UTILS='UTILITY_1 UTILITY_2' install
