Add README for underscore

underscore/README.markdown

@@ -0,0 +1,47 @@
+# underscore
+--
+Package underscore contains the source for the underscore utility-belt library for JavaScript.
+
+	import (
+		_ "github.com/robertkrimen/otto/underscore"
+	)
+	// Every Otto runtime will now include underscore
+
+http://underscorejs.org
+
+https://github.com/documentcloud/underscore
+
+By importing this package, you'll automatically load underscore every time you create a new Otto runtime.
+
+To prevent this behavior, you can do the following:
+
+	import (
+		"github.com/robertkrimen/otto/underscore"
+	)
+
+	func init() {
+		underscore.Disable()
+	}
+
+## Usage
+
+#### func  Disable
+
+```go
+func Disable()
+```
+Disable underscore runtime inclusion.
+
+#### func  Enable
+
+```go
+func Enable()
+```
+Enable underscore runtime inclusion.
+
+#### func  Source
+
+```go
+func Source() string
+```
+Source returns the underscore source.