Add project transferring #57
Description
Give an opportunity to transfer projects to other accounts.
So, after user clicks on transfer project, he gets a link that allows to claim it. After user has claimed it, the transfer must be accepted by a link sent to previous owner. However, it should be checked by admins in case the project is verified. After transfer, all keys should be reset as well. And that should be enough to provide a secure option to transfer projects.