update readme

Author: nieomylnieja

README.md

@@ -76,6 +76,13 @@ chmod 700 install.bash
 ./install.bash --help
 ```
 
+*NOTE:* If you install sloctl outside of your PATH you must also
+change its permissions for the binary to be executable!
+
+```bash
+chmod +x <PATH_TO_SLOCTL>
+```
+
 ### Prebuilt Binaries
 
 The binaries are available at