Add colon

Signed-off-by: Leo Siepel <[email protected]>

bundles/org.openhab.binding.irobot/README.md

@@ -23,7 +23,7 @@ It's not known, however, whether the password is eternal or can change during fa
 If you have issues getting the password make sure there are no other devices like your smartphone communicating with the robot.
 You can also try using [these python scripts](https://github.com/NickWaterton/Roomba980-Python) to get the password.
 
-**NOTE** For file based configuration storing the password is essential.
+**NOTE:** For file based configuration storing the password is essential.
 Once the password is populated in the MainUI Thing's codetab, you must copy that into the [config files](#irobotthings-example) in order for it to persist.
 Without this the Roomba will appear to work temporarily, but as soon as the Things file is edited, the password is lost and the button needs to be pushed again.