Add execution time to transient prompt

Also remove "VBE" from the transient prompt code I yoinked.

.zshrc

@@ -37,8 +37,8 @@ _prompt () {
     local retval=$?
 
     # Echo compact prompt
-    if (( $_vbe_prompt_compact )); then
-        echo '\e[32m\e[0m '
+    if (( $_prompt_compact )); then
+        echo "\e[1;30;42m `date +%H:%M:%S` \e[32;40m\e[0m "
         return
     fi
 
@@ -58,15 +58,15 @@ _zle-line-init() {
 
     # If we received EOT, we exit the shell
     if [[ $ret == 0 && $KEYS == $'\4' ]]; then
-        _vbe_prompt_compact=1
+        _prompt_compact=1
         zle .reset-prompt
         exit
     fi
 
     # Line edition is over. Shorten the current prompt.
-    _vbe_prompt_compact=1
+    _prompt_compact=1
     zle .reset-prompt
-    unset _vbe_prompt_compact
+    unset _prompt_compact
 
     if (( ret )); then
         # Ctrl-C