Add logistic connections

[natafaye]

I'd really like to be able to set logistic conditions with factorio-blueprint. Here's a way that appears to work nicely and has essentially no effect on setting circuit conditions.

I added a type property to CombinatorData that can be left undefined, or set to "logistic" or "circuit".

Side Note: I think it would make more sense to rename the type to ConditionData, since it's used for all conditions, not just on combinators.

If it's left undefined, the condition will be a circuit condition.

In data generation, I added the connect_to_logistic_network property, and put in a ternary operator to switch between naming the condition property "circuit_condition" or "logistic_condition".

I added a test for setting the logistic condition and updated the documentation to make it clear that conditions can be circuit or logistic and aren't just for combinators.