WP 2.4 Stuff

XML-RPC
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- WLW manifest file update, ticket 5023- Provide post status, ticket 4982- Encoding, ticket 4794
- Fix wp.newCategory, ticket 4603- Better docs, ticket 4600
- Add wp.deleteCategory, 4599
- Versioning, or feature support indicators, ticket 4590
- Limit pingback DDOS, ticket 4137
- ? Struct of struct mw_getCategories, ticket 3994
- More filters, ticket 3525
- ? Enclosures, ticket 3405
- ? Show pingback error messages, ticket 2933
- ? Comment pingback, ticket 2700


- Close the following tickets? 4874, 4115, 4112, 3995