Relax url validation in add cmd a bit (#157)

..so it is possible to add a video id from a mixed video/playlist url to the queue.

catt/cli.py

@@ -229,7 +229,7 @@ def cast_site(settings, url):
 @click.pass_obj
 def add(settings, video_url, play_next):
     cst, stream = setup_cast(settings["device"], video_url=video_url, action="add", prep="control")
-    if cst.name != stream.extractor or not stream.is_remote_file:
+    if cst.name != stream.extractor or not (stream.is_remote_file or stream.is_playlist_with_active_entry):
         raise CattCliError("This url cannot be added to the queue.")
     click.echo('Adding video id "%s" to the queue.' % stream.video_id)
     if play_next:

catt/stream_info.py

@@ -82,7 +82,7 @@ def is_playlist(self):
         return not self.is_local_file and "entries" in self._preinfo
 
     @property
-    def _is_playlist_with_active_entry(self):
+    def is_playlist_with_active_entry(self):
         return self.is_playlist and self._info
 
     @property
@@ -95,7 +95,7 @@ def video_title(self):
             return Path(self._local_file).name
         elif self._is_direct_link:
             return self._preinfo["webpage_url_basename"].split(".")[0]
-        elif self.is_remote_file or self._is_playlist_with_active_entry:
+        elif self.is_remote_file or self.is_playlist_with_active_entry:
             return self._info["title"]
         else:
             return None
@@ -104,18 +104,18 @@ def video_title(self):
     def video_url(self):
         if self.is_local_file:
             return "http://%s:%s/?loaded_from_catt" % (self.local_ip, self.port)
-        elif self.is_remote_file or self._is_playlist_with_active_entry:
+        elif self.is_remote_file or self.is_playlist_with_active_entry:
             return self._get_stream_url(self._info)
         else:
             return None
 
     @property
     def video_id(self):
-        return self._info["id"] if self.is_remote_file or self._is_playlist_with_active_entry else None
+        return self._info["id"] if self.is_remote_file or self.is_playlist_with_active_entry else None
 
     @property
     def video_thumbnail(self):
-        return self._info.get("thumbnail") if self.is_remote_file or self._is_playlist_with_active_entry else None
+        return self._info.get("thumbnail") if self.is_remote_file or self.is_playlist_with_active_entry else None
 
     @property
     def guessed_content_type(self):