-- Gave condition nodes a square shape; gave edges from actions to
dependencies to topics a dotted shape.
-- Partially fixed an issue in parseDependencies: a stack of topics
must be kept as a field in an instantiable class in order to not
associate actions with the wrong topics in some cases.
-- Updated unit tests in EnvironmentSpec.scala

Signed off by: Mark Farrell<markfarr2011@gmail.com>