Enhance tutorial 2

[auroranavas]

• Explain tyrlang conceptually. - the used parts of tyrlang.
• also explain the model (two networks, two apps per network, …)
• I do not understand the colors in the renders. Please comment! (How are they decided?)
• TTC needs to be briefly explained
• explain how different policies are set
• I think it is good to show that you can have a defender agent but clarify that this is not needed and does not really make a difference in this example.
• again explain entry_points, goals, and policy under the AgentSettings
• can we make a Graphviz render of the attack path?
• also for tutorial2 I would suggest to splitting the model creation into one file and the simulation into another.