Fix already marked articles was reshown bug

Since we search for matching states for articles to include or exclude
in a loop, we could not control the outer loop via default break/
continue. Python docs recommend using Exceptions and try/except
structures to realise that most conveniently.

https://docs.python.org/3/faq/design.html#why-is-there-no-goto

Related Task: [FS#138](https://fs.golderweb.de/index.php?do=details&task_id=138)

lib/redfam.py

@@ -515,45 +515,66 @@ class RedFamWorker( RedFam ):
         @type  filter_redirects  bool/None
 
         """
+
+        # Helper to leave multidimensional loop
+        # https://docs.python.org/3/faq/design.html#why-is-there-no-goto
+        class Continue(Exception):
+            pass
+
+        class Break(Exception):
+            pass
+
         # Iterate over articles in redfam
         for article in self.articlesList:
+
+            # To be able to control outer loop from inside child loops
+            try:
+
                 # Not all list elements contain articles
                 if not article:
-                break
+                    raise Break()
 
-            page = pywikibot.Page(pywikibot.Link(article), pywikibot.Site())
+                page = pywikibot.Page( pywikibot.Link(article),
+                                       pywikibot.Site() )
 
                 # Filter existing pages if requested with filter_existing=False
                 if page.exists():
                     self.article_remove_status( "deleted", title=article )
                     if filter_existing is False:
-                    continue
+                        raise Continue()
-            # Filter non existing Pages if requested with filter_existing=True
+                # Filter non existing Pages if requested with
+                # filter_existing=True
                 else:
                     self.article_add_status( "deleted", title=article )
                     if filter_existing:
-                    continue
+                        raise Continue()
 
                 # Filter redirects if requested with filter_redirects=True
                 if page.isRedirectPage():
                     self.article_add_status( "redirect", title=article )
                     if filter_redirects:
-                    continue
+                        raise Continue()
                 # Filter noredirects if requested with filter_redirects=False
                 else:
                     self.article_remove_status("redirect", title=article )
                     if filter_redirects is False:
-                    continue
+                        raise Continue()
 
                 # Exclude by article status
                 for status in exclude_article_status:
                     if self.article_has_status( status, title=article ):
-                    continue
+                        raise Continue()
 
                 # Only include by article status
                 for status in onlyinclude_article_status:
                     if not self.article_has_status( status, title=article ):
+                        raise Continue()
+
+            # Proxy loop control to outer loop
+            except Continue:
                 continue
+            except Break:
+                break
 
             # Yield filtered pages
             yield page