autofix: refactor katnetic front-end

Group the different subcommands into modules
autofix: add subcommands for dump automaton

Now available:

  - dump automaton policies: print the policy for each switch
  - dump automaton flowtables: print the flowtable for each switch
  - dump automaton [all]: print the policy and flowtable for each switch

So if you want to just look at the policies for abfattree-tables.kat

  ./katnetic.byte dump automaton policies examples/abfattree-tables.kat
Bugfix in to_table and some memoizing
Merge branch 'autofix' into start-from-vlan1

Conflicts:
	frenetic/katnetic.ml
Merge branch 'to-table-fix' into start-from-vlan1

Conflicts:
	frenetic/katnetic.ml