notmuch.el: Add documentation for notmuch-search-show-thread.

It's especially unkind to leave interactive functions without
documentation.

diff --git a/notmuch.el b/notmuch.el
index 9b23e3511fbd789e8aaca6ed9c374826b57e475f..b99ca02effade25fbaf8d12c45816c33e242e6cb 100644 (file)
--- a/notmuch.el
+++ b/notmuch.el
@@ -1012,6 +1012,7 @@ global search.
   (get-text-property (point) 'notmuch-search-thread-id))
 
 (defun notmuch-search-show-thread ()
+  "Display the currently selected thread."
   (interactive)
   (let ((thread-id (notmuch-search-find-thread-id)))
     (if (> (length thread-id) 0)