classic: Show th save button only if it's usable

There are some pros and cons to this, e.g. with this change, a user
with an expired login session might be confused about why they can
no longer save. On the other hand showing the "save to tiddlyhost"
button when a save is not possible is also potentially confusing.
Anyway, let's try it this way and see how we like it.

Closely related to the changes in the previous commit for issue

rails/tw_content/plugins/thost_upload_plugin.js.erb

@@ -196,10 +196,10 @@ if (config.shadowTiddlers.TiddlyHostIsLoggedIn == "yes") {
   // If user is logged in to Tiddlyhost then disregard the value of
   // the chkHttpReadOnly cookie and always show the edit buttons
   config.options.chkHttpReadOnly = false
-}
 
-// Add 'upload to tiddlyhost' button
-config.shadowTiddlers.SideBarOptions = config.shadowTiddlers.SideBarOptions
-  .replace(/(<<saveChanges>>)/,"$1<<thostUpload>>");
+  // Add the 'save to tiddlyhost' button after the regular save button
+  config.shadowTiddlers.SideBarOptions = config.shadowTiddlers.SideBarOptions
+    .replace(/(<<saveChanges>>)/,"$1<<thostUpload>>");
+}
 
 //}}}