Add new Pultosch functionality and related templates

Added a new package, "pultosch", which includes server-side functionality (pultosch.go) and HTML templates for the Pultosch (cashier) interface (pultosch.template.html and recentSpends.template.html). The update provides features such as transaction oversight and budget tracking for administrators utilizing transaction and spend infos ('specialSpend', 'spendData'). Through this addition, the application will now support a comprehensive overview of recent transactions (limit default is set to 10). This will allow admins to monitor these transactions more closely for better financial management.