update note about development branch

Signed-off-by: kim (grufwub) <grufwub@gmail.com>

README.md

@@ -12,7 +12,8 @@ I'm unemployed and work on open-source projects like this and many others for
 free. If you would like to help support my work that would be hugely
 appreciated 💕 https://liberapay.com/grufwub/
 
-WARNING: the development branch is filled with lava, fear and capitalism.
+WARNING: the (currently non-extant) development branch is filled with lava,
+         fear and capitalism.
 
 # Features