Update _yaourt

I have the next function in .zshrc:

      pacman () {
        /usr/bin/sudo /usr/bin/pacman $* && echo "$*" | grep -q "S\|R" && rehash
      }

And I have the next line in `/etc/yaourtrc`:

      PACMAN="/usr/bin/pacman"

But if I try to get autocomplite for `yaourt -Ss` (for example) it requires a sudo password. With this patch path to `pacman` (`PACMAN` variable) will be read from the configuration file and this command will not require the password.

It is a correct variant :)

src/_yaourt

@@ -186,7 +186,9 @@ _yaourt_completions_repositories() {
 # $cmd must be declared by calling function
 _yaourt_get_command() {
     # this is mostly nicked from _perforce
-    cmd=( "pacman" )
+    cmd=$( grep "^PACMAN=" "/etc/yaourtrc" \
+           && grep "^PACMAN=" "/etc/yaourtrc" | cut -c8- \
+           || echo "pacman" )
     integer i
     for (( i = 2; i < CURRENT - 1; i++ )); do
         if [[ ${words[i]} = "--config" || ${words[i]} = "--root" ]]; then