Integrate Metadata, Object Relocation and move S3 listing to the Metadata Server

What's Changed

• Implement object relocation. by @pspoerri in #42
• Integrate Metadata + Query S3 objects from the Metadata Server. by @pspoerri in #54
• GEDSFileHandle: Integrate mutex for I/O operations and cleanup interface. by @pspoerri in #61
• GEDS: Mark filehandles with an FD as local. by @pspoerri in #62
• Fix Python integration. by @pspoerri in #63

Full Changelog: v0.8.1...v0.8.2