add sql cli and explain it in the readme

README.md

@@ -42,7 +42,7 @@ nano capsulflask/__init__.py
 Run the app 
 
 ```
-FLASK_APP=capsulflask flask run
+flask run
 ```
 
 Run the app in gunicorn
@@ -50,8 +50,49 @@ Run the app in gunicorn
 .venv/bin/gunicorn --bind 127.0.0.1:5000 capsulflask:app
 ```
 
+-----
 
-# postgres database schema management
+## cli 
+
+You can manually mess around with the database like this:
+
+```
+flask cli sql -f test.sql
+```
+
+```
+flask cli sql -c 'SELECT * FROM vms'
+```
+
+This one selects the vms table with the column name header:
+
+```
+flask cli sql -c "SELECT string_agg(column_name::text, ', ') from information_schema.columns WHERE table_name='vms'; SELECT * from vms"
+```
+
+How to modify a payment manually, like if you get a chargeback or to fix customer payment issues:
+
+```
+$ flask cli sql -c "SELECT id, created, email, dollars, invalidated from payments"
+1, 2020-05-05T00:00:00, forest.n.johnson@gmail.com, 20.00, FALSE
+
+$ flask cli sql -c "UPDATE payments SET invalidated = True WHERE id = 1"
+1 rows affected.
+
+$ flask cli sql -c "SELECT id, created, email, dollars, invalidated from payments"
+1, 2020-05-05T00:00:00, forest.n.johnson@gmail.com, 20.00, TRUE
+```
+
+
+How you would kick off the scheduled task:
+
+```
+flask cli cron-task
+```
+
+-----
+
+## postgres database schema management
 
 capsulflask has a concept of a schema version. When the application starts, it will query the database for a table named
 `schemaversion` that has one row and one column (`version`). If the `version` it finds is not equal to the `desiredSchemaVersion` variable set in `db.py`, it will run  migration scripts from the `schema_migrations` folder one by one until the `schemaversion` table shows the correct version.
@@ -62,9 +103,9 @@ For example, the script named `02_up_xyz.sql` should contain code that migrates
 
 In general, for safety, schema version upgrades should not delete data. Schema version downgrades will simply throw an error and exit for now. 
 
+-----
 
-
-# how to setup btcpay server
+## how to setup btcpay server
 
 Generate a private key and the accompanying bitpay SIN for the bitpay API client.