hdf5 writer: revised error handling, version info, flushing

• Revise error handling: instead of catching exceptions when writing to file, they will be passed on, sending the Satellite into ERROR state which is more appropriate then an error message
• The latter uncovered an issue with the error handling in the Satellite in such cases which is fixed and tested for now
• The HDF5 file is flushed at configurable intervals
• Adds constellation version to the hdf5 file being written. Right now, this info resides in a new group with the name of the file writer and is the only info there.