Enhancement: Unit tests for datasources classes - Part 3

Unit tests of the OCFolderBackupLocalDataSource, OCRemoteOAuthDataSource, OCRemoteShareeDataSource, OCLocalShareDataSource,
OCRemoteShareDataSource, OCLocalSpacesDataSource, OCRemoteSpacesDataSource, OCLocalTransferDataSource, OCLocalUserDataSource,
OCRemoteUserDataSource, OCRemoteWebFingerDatasource classes have been done and completed.

https://github.com/owncloud/android/issues/4072
https://github.com/owncloud/android/pull/4143
