Joining the packet sources

[xoft]

I expect three or four phases. But the current one is too long and it actually makes sense to commit it in partial increments, because things still do work in each such increment. I don't want to work on this for a week and then find out someone has been fiddling with the code in the same place and we have code conflicts that I need to resolve first, before committing. It also gives others a chance to comment on the new style.