Significantly updates the Engineering guidebook (more explicitly the Atmos section) to have a lot more relevant and useful information.
Right now engineering has been getting update after update with no real change to the relevant guidebook entry. This has lead to a lot of out of date information and bad practices being prevalent in the guidebook, something that pains me to read.
* Kills PipeNode ConnectToContainedEntities and EnvironmentalAir with fire.
* Reaction IGasMixtureHolder is nullable.
* Reworks canisters
* Adds PortablePipeNode and PortPipeNode, which connect to each other.
