Kill the compdef; Introduce 'grh' alias for 'git reset HEAD'

plugins/git/git.plugin.zsh

@@ -36,8 +36,8 @@ alias ga='git add'
 compdef _git ga=git-add
 alias gm='git merge'
 compdef _git gm=git-merge
+alias grh='git reset HEAD'
 alias grhh='git reset HEAD --hard'
-compdef _git grhh=git-reset-head-hard
 
 # Git and svn mix
 alias git-svn-dcommit-push='git svn dcommit && git push github master:svntrunk'