Remove link to change email address

We never implemented this; the link goes to a 404.  And it's unlikely that we
will get to it soon, because we currently use email address as the unique
identifier for a user.

Since it can't be changed, we remove it from the 'Settings' tab entirely.
It's still visible in the sidebar, anyway.

(imported from commit a18c0726fb67baf04429a90e36a383cacd03ad8a)

templates/zephyr/settings.html

@@ -3,8 +3,6 @@
 <div class="row-fluid">
   <div id="current_settings" class="span9">
     <h1>Settings</h1>
-      <label>Email</label>
-      <b>{{ user_profile.user.email }}</b> <a href="/settings/change-email">(change?)</a><br /><br />
       <div id="API">
       <label>API Key</label>
       <div id="api_key_button_box">