Medical Vitals - Extract update logic to separate functions

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When merged this pull request will:

• Makes more sense IMO. Intent is for events to be used as API (IV medication/incompatible blood transfusions, for example).

Event deferral is just to keep any code from the events out of the vitals counter, but they can just be raised straight with no problems.

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[LinkIsGrim]

On another note:

• VAR_HEMORRHAGE doesn't have any usage (and I don't think it's API?)
• VAR_IN_PAIN could be replaced with a comparison with GET_PAIN_PERCEIVED > 0 (which is what is done in the state update, point is, we could drop the network update by doing a cheap comparison)

Drop 'em?