removed empty/unused 'completion' file and references

zshrc

@@ -7,7 +7,6 @@ else
   source $HOME/.zsh/interactive
   source $HOME/.zsh/exports
   source $HOME/.zsh/bindkeys
-  source $HOME/.zsh/completion
   source $HOME/.zsh/setopt
   PROMPT="UNCONFIGURED%# "
   return 1
@@ -17,7 +16,6 @@ source $HOME/.zsh/alias
 source $HOME/.zsh/interactive
 source $HOME/.zsh/exports
 source $HOME/.zsh/bindkeys
-source $HOME/.zsh/completion
 source $HOME/.zsh/setopt
 if [ $SYNTAX_HIGHLIGHT = true ]
 then