Add Demand unit to Consumers screen and include in Target explanation copy

[manumoreira]

This is how it should look like

Currently, we are not doing any filter by age or gender (mainly because the datasets we are using do not have that information) so the Consumer unit is always total population, we should change its default value to total population

[ismaelbej]

@manumoreira Currently "Consumer unit" is used in two places "Scenario Info"

and "Provider Info"

Should we replace them with "Demand unit" instead?

[manumoreira]

@ismaelbej exactly we should replace Consumer unit by Demand unit in these two places as well as in the review screen

.... BTW, why is per year there?... could you please delete that...