Remove changelog.md link

This file (changelog.md) no longer appears active; removing reference from README.md

README.md

@@ -43,7 +43,7 @@ reserves the right to change the license of future releases. Wondering what you
 AdminLTE 1.x can be easily upgraded to 2.x using [this guide](https://adminlte.io/themes/AdminLTE/documentation/index.html#upgrade), but if you intend to keep using AdminLTE 1.x, you can download the latest release from the [releases](https://github.com/ColorlibHQ/AdminLTE/releases) section above.
 
 ### Change log
-**For the most recent change log, visit the [releases page](https://github.com/ColorlibHQ/AdminLTE/releases) or the [changelog file](https://github.com/ColorlibHQ/AdminLTE/blob/master/changelog.md).** We will add detailed release notes to each new release.
+**For the most recent change log, visit the [releases page](https://github.com/ColorlibHQ/AdminLTE/releases).** We will add detailed release notes to each new release.
 
 ### Image Credits
 - [Pixeden](http://www.pixeden.com/psd-web-elements/flat-responsive-showcase-psd)