v1.40, June 12, 2014    -- Initial public release.
v1.42, June 19, 2014    -- Removed dependency on simplejson
v1.43, June 27, 2014    -- Fixed JSON handling issue
v1.44, July 3, 2014     -- Added show_tracks.py exampole
v1.45, July 7, 2014     -- Support for related artists endpoint. Don't used 
                           cache auth codes when scope changes
v1.50, August 14, 2014  -- Refactored util out of examples and into the main 
                           package
v2.301, August 19, 2014 -- Upgraded version number to take precedence over 
                           previously botched release (sigh)
v2.310, August 20, 2014 -- Added playlist replace and remove methods. Added auth
                           tests. Improved API docs
v2.310, January 05, 2015 -- Added session support
v2.3.1, March 28, 2015 --  auto retry support
v2.3.5, April 28, 2015 --  fixed bug in auto retry support
