While the correct usage would require an `in_time_zone` call, the code
can be simplified and the relationship between the current date and the
last `proposal.created_at + index.days` is now a bit easier to notice.
We use the beginning of the month as the date of the first action
because we expect all 8 actions to be created on the same month.
FIxed issue in last commit: supports controller were not correctly
filling the holes without data.
Fixed duplication in supports and successful supports controller using a
concer.
Successfull supports controller will fill the holes without data in the
same way that supports controller does.
Supports controller now fill the holes in the results: When there are no
supports collected for one interval it takes the accumulated value from the
previous one.
Data starts in the publication date.
