Added add-zsh-hook support to themes

I added add-zsh-hook support to the themes that didn't have it already.
This allows the themes to co-exist with plugins and lib/termsupport.

themes/kolo.zsh-theme

@@ -7,7 +7,7 @@ zstyle ':vcs_info:*' unstagedstr '%F{yellow}●'
 zstyle ':vcs_info:*' check-for-changes true
 zstyle ':vcs_info:(sv[nk]|bzr):*' branchformat '%b%F{1}:%F{11}%r'
 zstyle ':vcs_info:*' enable git svn
-precmd () {
+theme_precmd () {
     if [[ -z $(git ls-files --other --exclude-standard 2> /dev/null) ]] {
         zstyle ':vcs_info:*' formats ' [%b%c%u%B%F{green}]'
     } else {
@@ -19,3 +19,6 @@ precmd () {
 
 setopt prompt_subst
 PROMPT='%B%F{magenta}%c%B%F{green}${vcs_info_msg_0_}%B%F{magenta} %{$reset_color%}%% '
+
+autoload -U add-zsh-hook
+add-zsh-hook precmd  theme_precmd