- Focus
  ==> Work on the quotiented graph
  ==> Highlight the roots
  ==> Show exactly the selected subgraph
  ==> Generate all focus graphs (and show to which nodes they correspond)

- Viwever: key bindings + redraw optimizations + tooltips
- Graph creation: focus on a package
- Bug in Lwt_pool (???)

- Fix bug in eliom client (unwrapping elements)
- Fix performance issue in Ocaml

=============================

- smarter way to remove conflicts at the initial stage
    exist d, forall p, p in d -> exist q, q ## p /\ f ==> q

- try to associate a set of package and virtual packages to each
  disjunctive depends and conflict cliques

- find a way to automatically remove uninteresting nodes
  ===> not part of a non-trivial conflict clique
       (or only conflicts with nodes with no other conflicts?)
       + no package depends on it
       (and does not depend on any package?)

- improve algorithm for finding cliques of conflicts
  ==> Data Reduction and Exact Algorithms for Clique Cover
         http://theinf1.informatik.uni-jena.de/ecc/
      A note on the problem of reporting maximal cliques
  ==> clique partitioning
  ==> Exact Coloring of Real-Life Graphs is Easy
      New Graph Coloring Algorithms
      RESEARCH ON GREEDY CLIQUE PARTITION-GCP ALGORITHM (?)

  ====> we want to cluster clique
      => biclique covering
      Fast Exact and Heuristic Methods for Role Minimization Problems
      Confluent Layered Drawings
      Biclique Edge Cover Graphs and Confluent Drawings (?)
      Confluent Drawings: Visualizing Non-planar Diagrams in a Planar Way

- generate directly a dot file with position informations

- remove some edges that can be obtained by transitivity
- investigate the edges that was not removed

====
- what can we say about updates: desemphasize edges that are unchanged