Possibility to update variable during simulation (previously only
rule activity could be updated)
Updating manual
Merge branch 'master' of git@github.com:jkrivine/KaSim.git

Conflicts:
	grammar/eval.ml
	main/main.ml
Updating manual
Updatable variables
TODO: missing recomputation of dependencies
Value passing style for $UPDATE effects
Updating manual
Implementing look up stategy.
Bigger logs.
Merge branch 'master' of github.com:jkrivine/KaSim
Bug correction "nl_pos_upd"
Module to profile story computation.
Profiling info for weak compression.
Correcting dates.
Merge branch 'master' of github.com:jkrivine/KaSim
Cleaning logging messages.
Espacing profiling steps.
profiling.
Better constraint propagation in weak compression:
Look down when an event is removed to see whether there is remaining only one
to do the job
Completing unexhaustive pattern matching.
Bug fix in the look down propagation (stories)
Better constraint propagation.
Bug correction: KaSim was not generating a "free" script in rules of the
form 'rule 1' A(y,z!0),K(x!0)->A(y!0,z),K(x!0)