[#710] Add IATIProjectResource.sync_owner field
[#710] Add IATIProjectResource.sync_owner field

Set Cordaid and RAIN as "sync owner" for _ALL_ their respective projects.

For RAIN remove any benchmark data, since there's no reference to
categories.

Fix imports.

akvo/akvo-rsr,akvo/akvo-rsr,akvo/akvo-rsr,akvo/akvo-rsr