feat: update analytics so to meet IABv2 requirements

- https://iabtechlab.com/wp-content/uploads/2017/12/Podcast_Measurement_v2-Dec-20-2017.pdf
  - no IP address is ever stored on the server. Only aggregate data is stored in the dababase.
  - rolling 24-hour window
  - castopod does not do pre-load
  - IP Blacklisting https://github.com/client9/ipcat
  - user-agent Filtering https://github.com/opawg/user-agents
  - ignores 2 bytes range "Range: 0-1" (performed by official Apple iOS Podcast app)
  - in case of partial content, adds up all requests to check >1mn was downloaded
  - identifying Uniques is done with a combination of IP Address and User Agent
- add AMcharts
- add some graphs
- add regions to analytics
- add ipcat blacklist
- enhance useragents performances
- add filesize and header size in order to calculate 1mn downloads
- update publisher ID3 field
- update castopod icon
- add disclaimer and warning import form translation
- update docs/setup-development.md

closes #10

app/Models/AnalyticsPodcastsModel.php

@@ -0,0 +1,55 @@
+<?php
+
+/**
+ * Class AnalyticsPodcastsModel
+ * Model for analytics_podcasts table in database
+ * @copyright  2020 Podlibre
+ * @license    https://www.gnu.org/licenses/agpl-3.0.en.html AGPL3
+ * @link       https://castopod.org/
+ */
+
+namespace App\Models;
+
+use CodeIgniter\Model;
+
+class AnalyticsPodcastsModel extends Model
+{
+    protected $table = 'analytics_podcasts';
+
+    protected $allowedFields = [];
+
+    protected $returnType = \App\Entities\AnalyticsPodcasts::class;
+    protected $useSoftDeletes = false;
+
+    protected $useTimestamps = false;
+
+    /**
+     * Gets all data for a podcast
+     *
+     * @param int $podcastId
+     *
+     * @return array
+     */
+    public function getDataByDay(int $podcastId): array
+    {
+        if (!($found = cache("{$podcastId}_analytics_podcast_by_day"))) {
+            $found = $this->select('`date` as `labels`')
+                ->selectSum('`hits`', '`values`')
+                ->where([
+                    '`podcast_id`' => $podcastId,
+                    '`date` >' => date('Y-m-d', strtotime('-1 year')),
+                ])
+                ->groupBy('`labels`')
+                ->orderBy('`labels``', 'ASC')
+                ->findAll();
+
+            cache()->save(
+                "{$podcastId}_analytics_podcast_by_day",
+                $found,
+                14400
+            );
+        }
+
+        return $found;
+    }
+}