Added various fixes to networks view including the ability to visualize per-network graphs
Local hosts dumps (before purging) are now handled properly again.
This commit adds protocol visualization in the Historical tab
of the network flows view, therefore enabling for better
analysis of per-network traffic.
This commit changes the flows display script so that it adds a navigation
bar when flows are grouped by network and allows to access a Historical
tab showing the traffic volume chart for that network.
This addresses issue #31.
