Fix up goals/groups for vaccines

[djay]

little while back they adjusted the population for each group so it now covers 72M ie whole population.

Main change is that general population has increased to include kids (except those in the student 12-17 group).

it would be good to change the group vac plots

• re-label the groups to make it clear
• have a line for whole of thailand
• cover all 3rd and 4th boosters into one category. ie still classify 2nd dose as vaccinated.

[djay]

mostly done in https://github.com/djay/covidthailand/commit/d73fd524020bacf2d04010b4375791153865facd