add readme

README.md

@@ -2,4 +2,29 @@
 
 [![Build Status](https://drone.deadbeef.codes/api/badges/steven/ynab-portfolio-monitor/status.svg)](https://drone.deadbeef.codes/steven/ynab-portfolio-monitor)
 
-Track your securities in YNAB for account types and update your balance automatically.
+Track your securities in YNAB for account types and update your balance automatically.  For each configured account, it will update the balance from your broker in YNAB every 6 hours by creating / editing a transaction named "Capital Gains or Losses".  On days that exchanges are closed, it will not do anything.  The end result is that there will be transaction each day with payee "Capital Gains or Losses" in YNAB for each account you configure, which allows tracking your account balance over time.
+
+### Example docker-compose.yml
+
+The values below are examples only.  You can configure as many account pairings as you want using environment variables in a continuous series starting from 0 as shown below.  Two example accounts are configured ending in _0 and _1 but a third can be added by adding account numbers/ID with _2.
+
+```yaml
+version: '3.8'
+
+services:    
+
+  ynab-portfolio-monitor:
+    image: registry.deadbeef.codes/ynab-portfolio-monitor:latest
+    restart: always
+    environment:
+      - questrade_refresh_token=4dsO6652dS3cxtcctscd3ds4Df2E0
+      - questrade_account_0=51000001 # TFSA
+      - questrade_account_1=51000002 # RRSP
+      - questrade_ynab_account_0=731af51e-cb40-4d4a-8094-8654e59e11fc # TFSA
+      - questrade_ynab_account_1=78e76e45-2fbe-4ab1-84e9-64ba0996d015 # RRSP
+      - ynab_budget_id=76566452-67ff-4642-99d1-47d752216fb3
+      - ynab_secret=98Q_J655F_TAyGnhCCDS4uqRe4R5654DT2d-ZXdssZ
+    volumes:
+      - /data/ynab-portfolio-monitor-data:/data
+
+```