Correct minor grammatical error in English chapter 2

[schultzdavid]

Replacing "and" with "that", as that's in all likelihood what was meant and makes the most sense:

Change

Exemplary technologies in these works **and** have since become central to the Libertarian community are immersive virtual worlds...

to

Exemplary technologies in these works **that** have since become central to the Libertarian community are immersive virtual worlds...