[pymapistore]: Fix get_properties behaviour (no arguments returns available properties, empty list returns no properties)
[mapistore-python]: Add return value check and memory allocation in get_available_properties
[pymapistore]: Correct MID assignation in folder.c
[mapistore-python][sample-backend]: enable get and set properties for attachments
[mapistore-python][sample-backend]: fix set_properties and save (changes in folders and messages didn't have any effect)
[mapistore-python][sample-backend]: implement delete_message (hard deletion)
[mapistore-python][sample-backend]: fix attachment ID behaviour, use attachment cache and add set_properties
[mapistore-python][sample.py]: include "next_aid" in message entries
[mapistore-python][sample-backend]: implement create_attachment
[mapistore-python][sample.py]: fix white spaces and line breaks
[pymapistore]: include attachment ID in Python bindings
[python-backend][sample.py]: add destructor so objects in the cache are cleaned
[mapistore-python]: implement ROPSaveChangesAttachment
[mapistore-python][sample.py]: Implement RopGetValidAttachments in OpenChange
[sample.py]: Fix typos
[pymapistore]: Modify "attachments" iterator to fit the attachment ID behaviour
[mapistore-python][sample-backend]: Implement move_copy_messages
[mapistore-python][sample-backend]: implement delete_message (hard deletion)
[pymapistore]: correct input type for py_MAPIStoreFolder_create_folder
[mapistore-python][sample-backend]: Implement move and copy folder