Update README.md

Author: daelsepara

README.md

@@ -39,6 +39,7 @@ ISBN 0 7497 1486 7
 - Press **r** or **R** to restore progress from a save file
 - Press **s** or **S** to save current progress to a file
 - Press **h** or **H** or **?** lists the commands **G**/**C**/**I**/**S**/**R**/**Q** and what each does
+- Press **u** or **U** to use a **healing salve**, if you have it
 
 ## Bugs