organize icons

lib/views/_form.html

@@ -30,8 +30,8 @@
       {% if slackConfigured() %}
       <span class="input-group input-group-sm input-group-slack extended-setting m-r-5">
         <div class="input-group-addon">
-          <img id="slack-mark-white" src="/images/slack/mark-monochrome_white.svg" width="18" height="18">
-          <img id="slack-mark-black" src="/images/slack/mark-monochrome_black.svg" width="18" height="18">
+          <img id="slack-mark-white" src="/images/icons/slack/mark-monochrome_white.svg" width="18" height="18">
+          <img id="slack-mark-black" src="/images/icons/slack/mark-monochrome_black.svg" width="18" height="18">
           <input class="" type="checkbox" name="pageForm[notify][slack][on]" value="1">
         </div>
         <input class="form-control" type="text" name="pageForm[notify][slack][channel]" value="{{ page.extended.slack|default('') }}" placeholder="slack-channel-name"