docs: update readme

Author: pemrouz

README.md

@@ -2,12 +2,24 @@
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-Allows connecting a Ripple node to other external services
+Allows connecting a node to external services. For example, when a resource changes, it could update a database, synchronise with other instances over AMQP, or pump to Redis. 
 
 ```js
 ripple = require('rijs')({ db: 'type://user:password@host:port/database' })
 ```
 
 It destructures the connection string into an object, looks up the `type` in `ripple.adaptors`, then passes that function the connection string as an object, and stores the result under `ripple.connections`. 
 
-You must register any adaptors you wish to use separate to this module. An adaptor is a function that takes the connection string as an object, creates an active connection and returns and object of four crud functions: `{ push, update, remove, load }`. These hooks will be invoked when the corresponding event occurs. 
+```js
+ripple.connections.push(
+  ripple.adaptors[type]({ type, user, database, port, host, password })
+)
+```
+
+You must register any adaptors you wish to use separate to this module. An adaptor is a constructor function that takes the connection string as an object, creates an active connection and returns an object of functions for each possible change type: `{ add, update, remove }`. These hooks will be invoked when the corresponding event occurs.
+
+```js
+ripple.on('change', ({ key, value, type }) => 
+  ripple.connections.map(con => 
+    con[type](res, key, value)))
+```