Fix PATH manipulation bug in bash profile

This bug caused entries to not be removed if they were already present
in the beginning of the list before being prepended. This could lead to
duplication of entires, usually this ended up being /usr/local/bin.

dotfiles/.config/bash/profile

@@ -36,7 +36,7 @@ export VIMINIT='let $MYVIMRC="$XDG_CONFIG_HOME/vim/vimrc" | source $MYVIMRC'
 prepend_dir() {   # 1: dir to add, 2: variable to manipulate
     [ -d "$1" -a -n "$2" ] || return
     local list="${!2}"                      # capture current value
-    list=${list#"$1sep"}                    # remove dir from beginning
+    list=${list#"$1:"}                      # remove dir from beginning
     list=${list//":$1:"/:}                  # remove dir from middle
     list=${list%":$1"}                      # remove dir from end
     printf -v "$2" "$1${list:+":$list"}"    # add in front (use : only if empty)