mutt: use default status format

The default status format plays nicely with the colour scheme background
change to dark hard and with brighter emacs and vim status line
background.

mutt/.mutt/muttrc

@@ -3,9 +3,6 @@
 # Colour scheme
 source ~/.mutt/gruvbox-theme
 
-# Status line
-set status_format="Mutt: %f [Msgs:%?M?%M/?%m%?n? New:%n?%?d? Del:%d?%?F? Flag:%F?%?t? Tag:%t?%?p? Post:%p?%?b? Inc:%b? Size:%l]___(%s)_%>_(%P)___"
-
 # Speed
 set sleep_time = 0