Merge pull request #44 from guardian/remove-v1-features

Remove legacy features
Update README.md
Add the ability to retrieve podcast
Merge pull request #43 from guardian/add-tag-podcast

Add the ability to retrieve podcast
Further examples
Update README.md
Further examples
Update README.md
Update tag tests
Update sections tests
Update search tests
Update collection item tests
This need not be lazy
Improve tag tests
Improve sections tests
Update item tests
Name tests
Time serialisation is tested elsewhere
Test most viewed
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