Categories - Spending report

[snurby7]

With #36 closing out in favor or spinning this off. Build out the logic in the SpendingReportByCategory component so that it can can do the following

• Aggregate the past 3 months to get an overall average of spending (both inflow/outflow) to a given category and organize it in some useful way. Ensure that the hardcoded three months is in one place so it can easily be replaced with a configurable amount soon.