Stats functions, round 2

[kenirwin]

• [x] add a ./stats command line shortcut to ./scripts/usageReport
• [x] add cmd-line stats options for day-level reporting
• [x] add cmd-line option for --start-date and --end-date
• [x] add a /stats route for web display of stats reporting

[kenirwin]

All but web route done in #74

[kenirwin]

added web /stats route in #78 (minimal, text-only display)