don't add metadata-referenced WordPress items to the ref-set.

change note-getter mocking to use MagicMock assignment in test setUp instead of per-method patching.
change more mocking to use MagicMock assignment instead of per-method patching.
moved test notes content to separate files.
indent
moved expected post content to separate file.
moved expected published note content to separate file.
fix docstring
added note-title processing hook to WordPress item initialization from Evernote.
using the hook to populate filename for image attachment items.
added note-resources processing hook to WordPress item initialization from Evernote.
using the hook to populate image data and mimetype for image attachment items.

also changed a couple of classmethod to staticmethods, and added with_resource_data flag to getNote from Evernote.
fix bug with &nbsp; entities in XML markup.
bug fix with None URL
implemented image upload in Evernote-WordPress adaptor.
forgot the test data for latest tests.