melvidoni/rsppfp: rsppfp v1.0.4

Stable release with minor bug fixes. Released February 2019.

• Fixed bugs for missing nodes on both transformation algorithms.
• The numeric or integer attributes on graphs with multiple attributes are no longer converted to characters. They are parsed to the generic numeric format.
• Minor wording changes on warnings and error messages.
• Updates to the get_shortest_path() function, to improve its functionality.