setup instructions in the readme
lots of documentation
Alphabetize customer list
Minor edits

- Add balances to customers list
- Add “Balance:” string to balance shown in top bar
- Change “delivery” text to “pickup”
- Allow negative number to be input into credit/debit
Adding pickup location to customer, order, and receipt. Kind of hackily using the delivery_notes field to contain either "Wallingford" or "Crown Hill" to indicate pickup location