Encoding issues when interacting with Blazegraph via py4jps

[markushofmeister]

There are encoding issues with non-ascii characters when interacting with Blazegraph from Python agents via the RemoteStoreClient of the JPS_BASE_LIB. For example, when uploading unit symbols like £, °, °C, or µg the Blazegraph GUI will display odd characters. The same odd characters will be returned when querying for those symbols.
Likely this encoding issue happens somewhere at the Python - Java interface, as uploading the entire ontology of units of measure rdf file using the RemoteStoreClient natively in Java does not face any of these issues.

The current workaround consists of

1. uploading all units with special characters at the start of relevant agents (to minimise instantiation of non-ascii Literals, as the instantiation seems to be inconsistent and previously produced different odd character sets), e.g. here
2. decode unit symbols upon retrieval, e.g. here

Fore the visualisation this has been addressed by PR #466 (Issue #513)