Implement NetStream

[Denneisk]

Until Garry finds it worthwhile to do so, there should be a unified method of sending large amounts of data to a player to deduplicate these constructs (of which >=2 exist to my knowledge). The easiest way to do this is to implement NetStream like AdvDupe2 and other addons do.

Also, unreliable NetStream when?

Issues referencing this topic:
#1040
#1858
#2603

[Denneisk]

#2932