Add description to docs

Author: devongovett

readme.md

@@ -115,6 +115,11 @@ Type: `Boolean`
 Default: `false`   
 Description: *If set to true, self-closing tags will trigger the `onclosetag` event even if `xmlMode` is not set to `true`. NOTE: If `xmlMode` is set to `true` then self-closing tags will always be recognized.*
 
+### `sourceLocations`
+Type: `Boolean`
+Default: `false`
+Description: *If set to true, AST nodes will have a `location` property containing the `start` and `end` line and column position of the node.*
+
 ## License
 
 [MIT](LICENSE)