Update inconsistencies in output variable names in time series

[p-robot]

Fix minor inconsistencies in the names of the output columns in time series files. The following is the suggested changes to include in the next release. Suggested updated defintions for output variables beginning with the following prefix:

• total_ : cumulative measures until the day in question such as total_death, total_infected, total_recovered, etc.
• daily_ : daily incidence measures such as daily_death, daily_infected ("incidence"), daily_hospitalisation (hospital admissions)
• n_ : measures that can be ambiguous and are not necessarily incident measures or cumulative measures (users should refer to documentation for description) such as n_quarantine (current number of people in quarantine or self-isolation), n_hospital (current number of individuals in hospital).