A little cleanup of the XML settings file.

- Remove comments. They're from an old version and not very useful.
- Set default max_number.
- Set a restrictive filename policy. I needed it before for some
  podcasts but if I'm not sure why.

poca.xml

 <poca version="0.8">
   <!-- Please see detailed configuration documentation online:
      https://github.com/brokkr/poca/wiki/Configuration -->
-  <!-- The meaning of the settings options are briefly as follows:
-    * base_dir: Directory containing the individual subscription folders
-    * id3encoding: Encoding to use on metadata (utf8 or latin1)
-    * id3removev1: Should we remove id3v1, only keeping v2 (yes or no)
-    * useragent: _Fallback_ user agent if connection is rejected for
-      default python user agent. Leave empty not to use a fallback.
-    * email logging setup not included by default, see wiki for details.
-    -->
   <settings>
     <base_dir>./Podcasts</base_dir>
+    <filenames>restrictive</filenames>
     <id3encoding>utf8</id3encoding>
     <id3removev1>yes</id3removev1>
     <useragent/>
   </settings>
-  <!-- Defaults take the same options as any single subscription. A
-    setting here, e.g. max_number, is applied to all subscriptions but
-    always overruled by sub-specific settings. Non-overruling settings in
-    metadata and filters are combined, e.g. a sub-specific 'artist' tag and
-    a global 'genre' tag -->
   <defaults>
-    </defaults>
+    <max_number>5</max_number>
+  </defaults>
   <subscriptions>
-    <!-- The meaning of the subscription options are brifly as follows:
-        * category: A category attribute on a subscription tag is helpful in
-                    organizing the output of 'poca-subscribe list'.
-        * state: A state attribute is either 'active' or 'inactive'. inactive
-                 subs are not updated. subs without state attribute are active.
-        * title: Name used for the folder of the subscription (required)
-        * url: The address of the rss feed (required)
-        * max_number: Max number of files to keep in subscription (optional)
-        * from_the_top: Get oldest files first, not newest (optional)
-        * metadata: Override id3 header fields with these values
-          (see https://github.com/brokkr/poca/wiki/ID3-frames for details)
-        * filters: Contains one or more of following tags (all optional)
-          * filename: Filename of the entry must match this string/regex
-          * title: Same as above, only for the title in the rss
-          * hour: The hour (24h-format) at which the entry was published.
-          * weekdays: Only entries from one of these weekdays (as integers)
-          * after_date: Only use entries published after date specified.
-        -->
     <subscription>
       <url>https://feeds.twit.tv/floss.xml</url>
       <title>Floss Weekly</title>
-      <max_number>4</max_number>
     </subscription>
     <subscription>
       <title>Bad Voltage</title>
       <url>https://www.badvoltage.org/feed/mp3/</url>
-      <max_number>4</max_number>
     </subscription>
     <subscription>
       <title>BSD Now</title>
       <url>https://www.bsdnow.tv/rss</url>
-      <max_number>4</max_number>
     </subscription>
     <subscription>
       <title>bsdtalk</title>
       <url>http://feeds.feedburner.com/Bsdtalk</url>
-      <max_number>3</max_number>
     </subscription>
     <subscription>
       <title>Hanselminutes</title>
       <url>https://hanselminutes.com/subscribe</url>
-      <max_number>5</max_number>
-      <rename divider="-" space="-">
-        <title/>
-        <date/>
-      </rename>
     </subscription>
     <subscription>
       <title>No Agenda</title>
       <url>http://feed.nashownotes.com/rss.xml</url>
-      <max_number>8</max_number>
+      <max_number>10</max_number>
     </subscription>
     <subscription>
       <title>Security Now</title>
       <url>https://feeds.twit.tv/sn.xml</url>
-      <max_number>4</max_number>
     </subscription>
     <subscription>
       <title>The Stack Overflow Podcast</title>
       <url>https://feeds.simplecast.com/XA_851k3</url>
-      <max_number>4</max_number>
-      <rename divider="-" space="-">
-        <title/>
-        <date/>
-      </rename>
     </subscription>
     <subscription>
       <title>This Developer's Life</title>
       <url>http://feeds.feedburner.com/thisdeveloperslife</url>
-      <max_number>3</max_number>
     </subscription>
     <subscription>
       <title>Reversim</title>
       <url>https://feed.reversim.com/</url>
-      <max_number>5</max_number>
     </subscription>
     <subscription>
       <title>On The Metal</title>
       <url>https://feeds.transistor.fm/on-the-metal-0294649e-ec23-4eab-975a-9eb13fd94e06</url>
-      <max_number>5</max_number>
     </subscription>
     <subscription>
       <title>The Pornhub Podcast with Asa Akira</title>
       <url>https://feeds.soundcloud.com/users/soundcloud:users:392064213/sounds.rss</url>
-      <max_number>5</max_number>
     </subscription>
     <subscription>
       <title>CoRecursive: Coding Stories</title>
@@ -120,13 +72,14 @@
     <subscription>
       <title>עושים היסטוריה עם רן לוי Osim Historia With Ran Levi</title>
       <url>https://www.spreaker.com/show/4227531/episodes/feed</url>
+      <max_number>8</max_number>
     </subscription>
     <subscription>
       <title>על הדרך</title>
       <url>https://feeds.buzzsprout.com/1738407.rss</url>
     </subscription>
     <subscription>
-      <title>The Lunduke Journal of Technology (private feed for nimrod+mailinglists@shore.co.il)</title>
+      <title>The Lunduke Journal of Technology</title>
       <url>https://api.substack.com/feed/podcast/462466/private/e8b25eee-6a46-497d-83b4-22142a663296.rss</url>
     </subscription>
   </subscriptions>