CHANGES IN VERSION 1.5.2
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  o MetaboSignal includes a new function: "MS_interactionType()". This function
  allows getting the interaction subtype between signaling nodes. The output
  matrix generated by this function can be used for "MetaboSignal_NetworkCytoscape()"
  and also for "MS_GetShortestpaths()".

  o "MS_GetShortestpaths()" has been modified and now the output shortest path(s)
  can be represented as a network-table (i.e. 2-column matrix).