[SERVER] CAP and PACELC theorem explanation

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Do we have any official documentation on  CAP or PACELC_theorem?   The only stuff I can find is what our SA have written but there is nothing posted on mongodb.com.   Our own SA written material says we are P+C (https://docs.google.com/presentation/d/1m52XODzQIHGAcgGaAod4e1NoTkcEQT4MIvVqSJCN0jQ/edit#slide=id.g90ae0d2d30_0_0 however wikipedia says we are P+A https://en.wikipedia.org/wiki/PACELC_theorem) and we don’t address PACELC (of which wiki says we are E+C). 

From JM: see my comment below. We do have such docs.

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