rewrite compatibility comments

home/prep

@@ -1,5 +1,5 @@
 #!/usr/bin/env false
-# for ash, dash, bash, and zsh.
+# for busybox ash, dash, bash, and zsh.
 
 if [ -r /etc/msystem ]; then
     # avoid sourcing /etc/profile because forking cygwin processes is awful.

home/shrc

@@ -1,5 +1,5 @@
 #!/usr/bin/env false
-# for ash, dash, bash, and zsh.
+# for busybox ash, dash, bash, and zsh.
 
 unset FANCY; _=: && [ -z $_ ] && FANCY=1 || FANCY=0 # detect zsh and bash
 if [ "$FANCY" = 0 ]; then . ~/.prep; fi # handle stuff like /etc/profile and $PATH

install

@@ -1,6 +1,5 @@
 #!/usr/bin/env sh
-# this script is compatible with following shells:
-# ash, dash, bash, zsh
+# for busybox ash, dash, bash, and zsh.
 
 VERBOSE="${VERBOSE-1}"