chore: update changelog

Author: QingWei-Li

Diff for: CHANGELOG.md

@@ -7,13 +7,6 @@
 * cover style, fixed [#381](https://github.com/QingWei-Li/docsify/issues/381) ([368754e](https://github.com/QingWei-Li/docsify/commit/368754e))
 * updated deps ([#337](https://github.com/QingWei-Li/docsify/issues/337)) ([a12d393](https://github.com/QingWei-Li/docsify/commit/a12d393))
 
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-### Features
-
-* add navigation plugin, closed [#180](https://github.com/QingWei-Li/docsify/issues/180) ([f78be4c](https://github.com/QingWei-Li/docsify/commit/f78be4c))
-
-
-
 <a name="4.5.7"></a>
 ## [4.5.7](https://github.com/QingWei-Li/docsify/compare/v4.5.6...v4.5.7) (2017-12-29)