to BioPAX L3: same pathways have different and not standard URIs in different files

[IgorRodchenkov]

@draeger This is related to https://github.com/PathwayCommons/cpath2/issues/205.

When a KEGG pathway with ID, e.g., hsa00010 is defined in its main biopax file (hsa_00010.owl), it has absolute URI like "path:hsa00010"; but when the same pathway is referenced from other files, e.g., hsa_00562.owl, its simplified/dummy version has a different URI "#pathhsa00010" (i.e,, "http://www.ra.cs.uni-tuebingen.de/software/KEGGtranslator/pathhsa00010") and the property looks like

<bp:pathwayComponent rdf:resource="#pathhsa00010" />

URIs of the same pathways must be exactly the same in all files, and be like "http://identifiers.org/kegg.pathway/hsa00010" instead.