-Fix: don't try to unload if there isn't anything to unload
-Codechange: Introduce save/load version naming
-Add: small matrix type
-Add: implementation of SharesMap and FlowStatMap
-Codechange: basic link graph
-Codechange: track capacity, supply, usage in link graphs
-Add: demand calculation for linkgraph
-Add: MCF solver for linkgraph
-Add: flow mapper for linkgraph
-Add: multimap implementation with guaranteed order between equal keys
-Feature: distribute cargo according to plan given by linkgraph
-Codechange: occasionally clear dead links from link graph
-Add: abstract implementation of linkgraph overlay for GUI
-Add: legend for linkgraph overlay
-Add: linkgraph overlay over main viewport
-Feature: linkgraph overlay for smallmap
-Feature: consider cargo waiting at other stations for rating at the origin station
-Feature: show cargo by next hops and final destinations in the station GUI
-Codechange: remove STR_STATION_VIEW_CARGO_RATINGS_TITLE
-Add: help texts for settings