Update README

Author: Nicolas Rodriguez

README.md

@@ -233,6 +233,7 @@ For example, this is a JSON version of an emitted RuntimeContainer struct:
 * *`whereNotExist $items $fieldPath`*: Like `where`, but returns only items where `$fieldPath` does not exist (is nil).
 * *`whereAny $items $fieldPath $sep $values`*: Like `where`, but the string value specified by `$fieldPath` is first split by `$sep` into a list of strings. The comparison value is a string slice with possible matches. Returns items which OR intersect these values.
 * *`whereAll $items $fieldPath $sep $values`*: Like `whereAny`, except all `$values` must exist in the `$fieldPath`.
+* *`parseBool $string`*: parseBool returns the boolean value represented by the string. It accepts 1, t, T, TRUE, true, True, 0, f, F, FALSE, false, False. Any other value returns an error. Alias for [`strconv.ParseBool`](http://golang.org/pkg/strconv/#ParseBool)
 
 ===