Add tool to manage RSS/Atom feeds

- weboob.tools.newsfeed a class representing a feed
 - the DLFP backend has been updated to use weboob.tools.newsfeed

weboob/tools/newsfeed.py

@@ -0,0 +1,48 @@
+import datetime
+import feedparser
+from weboob.backends.dlfp.tools import url2id
+
+class Entry:
+    def __init__(self, entry, url2id=None):
+        if url2id:
+            self.id = url2id(entry.id)
+        else:
+            self.id = entry.id
+        if entry.has_key("link"):
+            self.link = entry["link"]
+        if entry.has_key("title"):
+            self.title = entry["title"]
+        else:
+            self.title = None
+        if entry.has_key("author"):
+            self.author = entry["author"]
+        else:
+            self.author = None
+        if entry.has_key("updated_parsed"):
+            #updated_parsed = entry["updated_parsed"]
+            self.datetime = datetime.datetime(*entry['updated_parsed'][:7])
+        else:
+            self.datetime = None
+        if entry.has_key("content"):
+            self.content = entry["content"][0]["value"]
+        else:
+            self.content = None
+
+
+class NewsFeed:
+    def __init__(self, url, url2id=None):
+        self.feed = feedparser.parse(url)
+        self.url2id = url2id
+
+    
+        
+
+    def iter_entries(self):
+        for entry in self.feed['entries']:
+            yield Entry(entry, self.url2id)
+
+    def get_entry(self, id):
+        for entry in self.feed['entries']:
+            if entry.id == id:
+                return Entry(entry, self.url2id)
+