Use getpass to query 8tracks password (refs #31)
Fixed autologin related bug (refs #31)
Print messages when liking/favoriting mixes or tracks.
Modify search, liked_mixes command and various fixes.

client.py:
Removed do_search_next and do_liked_mixes_next command.
Empty line after search or liked_mixes now go to next page.
Added page information for liked_mixes
Modified help for search and liked_mixes.
PEP8 fixes.

api.py:
PEP8 fixes.

README.rst:
Removed search_next and liked_mixes_next description.
Modified search and liked_mixes description.
Merge remote-tracking branch 'upstream/master' into develop