Calculate total expenditure

Calculate total expenditure from other items instead of blindly taking
the ONS' data (as their numbers don't add up completely).
Added category codes to Items.csv
Added category lookup
Added totals column

Should be the last csv change in a while now
Calculate proportions based off UK averages
Now capable of working out proportions from any file
Broken proportions code, needs to be fixed
Vectorised CalculateOutgoings function
Fixed shiny interface
Uncommented accidently commented code
Calculate proportions slightly more nicely
Rewriting proportions in a more vector-y way
Comment on how to approach issue
Automatically grab customer id instead of taking it as an input
Now correctly calculates proportions
Cast proportions data
Correct incorrect value in Items.csv
Delete expenditurePerRegion.csv
Correctly generates standard deviation and mean
Remove surplus lines from csv files