- Reversed Imgur support.

Removed the Imgur-specific provider handling from 
[includes/db.php](/Users/tyemeclifford/Documents/GH/mediaplayer/includes/db.php), 
removed the admin upkeep Imgur counter/copy from 
[admin/index.php](/Users/tyemeclifford/Documents/GH/mediaplayer/admin/index.php), 
updated the upload hint in 
[admin/add.php](/Users/tyemeclifford/Documents/GH/mediaplayer/admin/add.php), 
cleaned the README mentions, and deleted provider_embed.php.

admin/index.php

@@ -95,7 +95,6 @@ $list_stmt->execute();
 $videos = $list_stmt->fetchAll();
 $youtube_timestamp_candidates = media_youtube_timestamp_candidate_count();
 $external_view_candidates = media_external_view_count_candidate_count();
-$imgur_view_candidates = media_imgur_view_count_candidate_count();
 $admin_total_views = total_video_views(false);
 
 $qs = fn($p) => '?' . http_build_query(array_filter(['q' => $search, 'page' => $p]));
@@ -242,8 +241,7 @@ render_head('Admin — TyClifford.com', '
               <h2 class="card-title">Correct external view counts</h2>
               <p class="hint">
                 Scrapes readable counts from supported providers and adds them to the media-site totals alongside local plays.
-                <?= $external_view_candidates ?> external video<?= $external_view_candidates === 1 ? '' : 's' ?> can be checked,
-                including <?= $imgur_view_candidates ?> Imgur-backed item<?= $imgur_view_candidates === 1 ? '' : 's' ?>.
+                <?= $external_view_candidates ?> external video<?= $external_view_candidates === 1 ? '' : 's' ?> can be checked.
                 Current database total: <?= h(view_count_label((int)$admin_total_views)) ?>.
               </p>
             </div>