Small bug fixes

- Delete from Releases when deleting artist/album
- Searcher - Size limits not quite working
- Searcher - 1st newznab used even if disabled
- Rutracker search stopped working for me, fixed by updating Beautiful
Soup. Moved bs4 and html5lib to lib and ensured (I think) it’s imported
from the right place

lib/html5lib/treeadapters/sax.py

@@ -0,0 +1,44 @@
+from __future__ import absolute_import, division, unicode_literals
+
+from xml.sax.xmlreader import AttributesNSImpl
+
+from ..constants import adjustForeignAttributes, unadjustForeignAttributes
+
+prefix_mapping = {}
+for prefix, localName, namespace in adjustForeignAttributes.values():
+    if prefix is not None:
+        prefix_mapping[prefix] = namespace
+
+
+def to_sax(walker, handler):
+    """Call SAX-like content handler based on treewalker walker"""
+    handler.startDocument()
+    for prefix, namespace in prefix_mapping.items():
+        handler.startPrefixMapping(prefix, namespace)
+
+    for token in walker:
+        type = token["type"]
+        if type == "Doctype":
+            continue
+        elif type in ("StartTag", "EmptyTag"):
+            attrs = AttributesNSImpl(token["data"],
+                                     unadjustForeignAttributes)
+            handler.startElementNS((token["namespace"], token["name"]),
+                                   token["name"],
+                                   attrs)
+            if type == "EmptyTag":
+                handler.endElementNS((token["namespace"], token["name"]),
+                                     token["name"])
+        elif type == "EndTag":
+            handler.endElementNS((token["namespace"], token["name"]),
+                                 token["name"])
+        elif type in ("Characters", "SpaceCharacters"):
+            handler.characters(token["data"])
+        elif type == "Comment":
+            pass
+        else:
+            assert False, "Unknown token type"
+
+    for prefix, namespace in prefix_mapping.items():
+        handler.endPrefixMapping(prefix)
+    handler.endDocument()