started using openpyxl and removed xlwt for excel operations.
reports home template json parse bug fixed
fixed customers' outstanding debt bug.
removed references to cashactivityreport; now using activityreport
activityreport generic object now called activity_model
activityreportview: spin out excel writing into its own view to ease testing.
activityreport: prepare to include all activities.
activityreport: all activities included and covered by tests.
I have started coding other activities into reports e.g cocoa-rebagged.