added alom/graphviz as dev dependency
graphviz visualisation class
visualisation exception
output format is detected based on input param.
added a check that tests if dot is executable in the tests
added a primitive rendering example
added visualisation interface
configuration value object
graphviz can render the properties
updated the example
changed the config to contain fillcolor
current state can be marked
updated examples
ran php-cs-fixer over the files
fixed type hints
fixed uses
fixed uses
removed echo from test
code cleanup
code cleanup