Change colors for nodes in the network plot (Enrichment module)

[gexijin]

Is your feature request related to a problem? What value do you see this adding? Please describe.
Change the color scheme in the network plots under the Enrichment module, so that up- and down- regulated pathways are represented by red and green, consistent with other parts of the app. Currently it is the opposite.

Note that there is a separate network plot in the pathway tab.