EPUB Output: Replace <center> tags with <div> tags since <center> is not valid XHTML

src/calibre/ebooks/epub/from_html.py

@@ -199,6 +199,10 @@ class HTMLProcessor(Processor, Rationalizer):
                 
         for tag in self.root.xpath('//form'):
             tag.getparent().remove(tag)
+            
+        for tag in self.root.xpath('//center'):
+            tag.tag = 'div'
+            tag.set('style', 'text-align:center')
                 
         if self.opts.linearize_tables:
             for tag in self.root.xpath('//table | //tr | //th | //td'):

todo

@@ -8,3 +8,7 @@
 * Rationalize books table. Add a pubdate column, remove the uri column (and associated support in add_books) and  convert series_index to a float.
 
 * Replace single application stuff with Listener from multiprocessing
+
+* Refactor add books to use a separate process named calibre-worker-add
+  - Dont use the process for adding a single book
+  - Use a process pool for speed