Update CHANGELOG

CHANGELOG.md

@@ -9,7 +9,9 @@ __New Features__
 
 __Document__
 * [#848](https://github.com/nghuuphuoc/bootstrapvalidator/pull/848): Update the [stringLength](http://bootstrapvalidator.com/validators/stringLength) document, thanks to [@Relequestual](https://github.com/Relequestual)
+* [#912](https://github.com/nghuuphuoc/bootstrapvalidator/issues/912): Add [Using language package](http://bootstrapvalidator.com/examples/using-language-package/) example
 * [#920](https://github.com/nghuuphuoc/bootstrapvalidator/issues/920), [#929](https://github.com/nghuuphuoc/bootstrapvalidator/pull/929), [#936](https://github.com/nghuuphuoc/bootstrapvalidator/pull/936): Update the [Changing the tooltip, popover's position](http://bootstrapvalidator.com/examples/tooltip-popover-position/) example, thanks to [@Arkni](https://github.com/Arkni)
+* [#979](https://github.com/nghuuphuoc/bootstrapvalidator/issues/979): Add [Rails usage](http://bootstrapvalidator.com/validators/stringLength/#using-with-rails-form) for stringLength validator
 
 __Language Packages__
 * [#827](https://github.com/nghuuphuoc/bootstrapvalidator/pull/827): Update Dutch language package, thanks to [@JvanderHeide](https://github.com/JvanderHeide)