Xcrawler

Added setting HTTP session parameters such as: cookies, SSL certificates, proxies
Added setting HTTP request parameters such as: header, body, authentication
Added support for file download
Added requests library to project requirements
Modified type of the timeout attribute of the Config class to a tuple: (connect timeout, read timeout)
The \__str\__ method of the Page class returns an unicode string in Python 3
Added examples: file download, setting session parameters and setting request parameters

Added support for Python 3
Improved converting links to absolute urls
Added a request attribute to the Page class

Added support for CSS selectors
Added examples of using CSS selectors
Added support for writing non-string attributes to an output file
Added support for safer extraction of incomplete data with a FallbackList
Added examples of using a FallbackList to extract incomplete data from a web page
Fixed bugs when converting ascii strings to unicode

The crawler exits Main thread after visiting web pages

Initial release