Remove unused __get_topology

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extra : rebase_source : c94e3e3a6362e55cafec59550223b9731c5feb08
Beginnings of revised topology handling

--HG--
extra : rebase_source : 1c1ae1bb3807ee68ff54f3ff6acdee74e62f65d0
Implementation of spotifyplugin
Removed function to retrieve top tracks, better to use existing libraries
Add album to queue, changes in method names
String formatting, exception is the callers responsibility
Spaces for indentation
Added docstrings
When adding title, make sure it's utf-8 encoded or it will fail
Remove quotes from __repr__

--HG--
extra : rebase_source : 757a6562afa29dfdca33b303f7caa06982c0d5c7
Refactor to use Subscription objects
Provide each subscription with its own queue

--HG--
extra : amend_source : c13baa7418c3031d0ebbc66d4b64b9ac2fd4501a
Event queues now parse XML
Some pylint fixes
resolving merge conflicts
Merging with master
Small fixes
*%@^£&^ pylint
Using weakrefs for mapping
Allow for custom queues to be passed to subscribe