Prevent change visibility of a repo in the UI when disallowed by billing plan

Fixes #486

- Extracts out the check plan logic and UI from the new repo page into its own directive (repo-count-checker)
- Adds the new directive to the repo settings panel
- Some additional UI improvements for the repo settings panel

static/css/directives/repo-view/repo-panel-settings.css

@@ -29,6 +29,18 @@
   margin-top: -7px !important;
 }
 
+.repo-panel-settings-element .repo-count-checker {
+  margin-top: 20px;
+}
+
+.repo-panel-settings-element .co-alert {
+  margin-bottom: 0px;
+}
+
+.repo-panel-settings-element .panel-body {
+  border-bottom: 0px;
+}
+
 @media (max-width: 767px) {
   .repo-panel-settings-element .delete-btn {
     float: none;