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/Controllers/Admin/AnalyticsData.php

@@ -0,0 +1,69 @@
+<?php
+
+/**
+ * @copyright  2020 Podlibre
+ * @license    https://www.gnu.org/licenses/agpl-3.0.en.html AGPL3
+ * @link       https://castopod.org/
+ */
+
+namespace App\Controllers\Admin;
+
+use App\Models\PodcastModel;
+use App\Models\EpisodeModel;
+
+class AnalyticsData extends BaseController
+{
+    /**
+     * @var \App\Entities\Podcast|null
+     */
+    protected $podcast;
+    protected $className;
+    protected $methodName;
+    protected $episode;
+
+    public function _remap($method, ...$params)
+    {
+        if (count($params) > 2) {
+            if (!($this->podcast = (new PodcastModel())->find($params[0]))) {
+                throw \CodeIgniter\Exceptions\PageNotFoundException::forPageNotFound(
+                    'Podcast not found: ' . $params[0]
+                );
+            }
+            $this->className = '\App\Models\Analytics' . $params[1] . 'Model';
+            $this->methodName = 'getData' . $params[2];
+            if (count($params) > 3) {
+                if (
+                    !($this->episode = (new EpisodeModel())
+                        ->where([
+                            'podcast_id' => $this->podcast->id,
+                            'id' => $params[3],
+                        ])
+                        ->first())
+                ) {
+                    throw \CodeIgniter\Exceptions\PageNotFoundException::forPageNotFound(
+                        'Episode not found: ' . $params[3]
+                    );
+                }
+            }
+        }
+
+        return $this->$method();
+    }
+    public function getData()
+    {
+        $analytics_model = new $this->className();
+        $methodName = $this->methodName;
+        if ($this->episode) {
+            return $this->response->setJSON(
+                $analytics_model->$methodName(
+                    $this->podcast->id,
+                    $this->episode->id
+                )
+            );
+        } else {
+            return $this->response->setJSON(
+                $analytics_model->$methodName($this->podcast->id)
+            );
+        }
+    }
+}