Fixed lazy, added naive local convergence.
Assembly OS X .DS_STORE fix.
Failed experiment with self-scheduling subproblems
Even lazier lazy, with configurable threshold.
Made implicit zero configurable.
Lazy not default, preparing for merge.

Also removed println statement in test.
Merge branch 'master' into lazier-lazy

Conflicts:

src/test/scala/com/signalcollect/psl/examples/AnimalClassification.scala
Removed debug output from test.
Merge branch 'lazier-lazy'