Add info and usage.

README.md

@@ -3,6 +3,8 @@ Bag Of Holding [![http://travis-ci.org/cliffano/bagofholding](https://secure.tra
 
 Bag Of Holding is an uncursed bag of various Node.js utility functions.
 
+It contains common functions used in various cliffano/* modules.
+
 Installation
 ------------
 
@@ -14,6 +16,17 @@ or specify it as a dependency in package.json file:
       "bagofholding": "x.y.z"
     }
 
+Usage
+-----
+
+    var bag = require('bagofholding');
+    bag.cli.*; // command-line tools utilities
+    bag.mock.*; // mock IO-related Node.js API
+    bag.obj.*; // object manipulation utilities
+    bag.text.*; // string manipulation utilities
+
+Check out the source code for a list of functions available for use.
+
 Colophon
 --------