Add summary stats for beds and ICU

[hnykda]

Followup for https://github.com/epidemics/covid/issues/192. Currently, we display total infections and active infections. This task is about extending this to:

• number of hospital beds needed
• number of deaths

See the https://github.com/epidemics/covid/issues/192 for proposals how to compute it. FE code should be mostly copy and paste of #287

E.g:

20-50M active infections, which means 1.1M to 3M hospital beds and 500k-1M ICU units are needed.

Overall there will be 200-800M infections, which can lead do 2-15M deaths.)

[janpipek]

Data should be exported here: https://github.com/epidemics/covid/issues/258

[hnykda]

from #258 we should have https://github.com/epidemics/epifor/pull/15/files#diff-6c3d86df2d4cc71a36d45075de3b7cb4R21712, i.e. max_percentage_of_infected_to_fill_icu_beds, which I don't know how to turn into the statistics above

[hnykda]

There is also this discussion: https://epidemicforecasting.slack.com/archives/CV1F9NB5K/p1585234929020700

[hnykda]

@mathijshenquet can we close this as it should be part of rates.txt added here, right?

[mathijshenquet]

No we still need beds_per_100k, you can assign me this though.

[mathijshenquet]

Actually I didnt read this well and what was described in this Issue is now included.

[hnykda]

Yeah, this is actually a frontend part, so this should be closed until it's on frontend.

[hnykda]

AFAIK blocked now until @jk3141 can give feedback