Revert "Revert "new table: remote storage connection for accounts""

This reverts commit beea16a2a93df95bf69baedd59e08cce9a9337cf.
Revert "Revert "save storage URL for remote storage""

This reverts commit 40dee35cf8ab41e22404bd6db494707a60501926.
delete remote storage connections when deleting account
Merge pull request #8 from Libertree/remotestorage

add table for remoteStorage connections