[Netron-graphlib] Subpoints on connections

[Francois V. <Fra...@sk...>]

Thanks for the bugs Martin, I'll have a look.

The subpoints on a connection is half done, it'll take another few days to
iron out some things. You should start thinking about sub-contracting
me...;-)

GraphML is indeed not a pudding and I fear that every new little addition
breaks the XML schema. That's why I kept pushing it behind.

Keep well, I.