webmagic-0.4.1

• Fix some concurrent problem causing the spider not exit after all pages are downloaded. #36
• #38 Use algorithm of https://code.google.com/p/cx-extractor/.

More support for ajax:

• #39 Parsing html after page.getHtml()
• #42 Add jsonpath support in annotation mode
• #35 Add more http info to page
• #41 Add more status monitor method to Spider