docs: Add Installing dependencies on Gentoo article.

source/docs/en/latest/developer/build-linux.markdown

@@ -24,6 +24,7 @@ Dependency installation instructions are available for the following distributio
 
 - [CentOS](install-dependencies-centos.html)
 - [Fedora](install-dependencies-fedora.html)
+- [Gentoo](install-dependencies-gentoo.html)
 - [Ubuntu](install-dependencies-ubuntu.html)
 
 ## Building HandBrake

source/docs/en/latest/developer/install-dependencies-gentoo.markdown

@@ -0,0 +1,31 @@
+---
+Type:            article
+Title:           Installing dependencies on Gentoo
+Project:         HandBrake
+Project_URL:     https://handbrake.fr/
+Project_Version: Latest
+Language:        English
+Language_Code:   en
+Authors:         Bradley Sepos <bradley@bradleysepos.com> (BradleyS)
+Copyright:       2016 HandBrake Team
+License:         Creative Commons Attribution-ShareAlike 4.0 International
+License_Abbr:    CC BY-SA 4.0
+License_URL:     https://handbrake.fr/docs/license.html
+---
+
+Installing dependencies on Gentoo
+=================================
+
+The following instructions are for [Gentoo](https://gentoo.org) Base System release 2.2 and [GNOME](https://www.gnome.org).
+
+Dependencies:
+
+- fribidi
+- jansson
+- libass
+
+Install dependencies.
+
+    sudo emerge --ask fribidi jansson libass
+
+Gentoo is now prepared to build HandBrake. See [Building HandBrake for Linux](build-linux.html) for further instructions.

source/docs/en/latest/table-of-contents.markdown

@@ -149,7 +149,7 @@ Table of contents
   - [Linux Flatpaks](developer/flatpak-repo.html)
 - Building HandBrake
   - [Building HandBrake for Linux](developer/build-linux.html)
-    - Installing dependencies on [CentOS](developer/install-dependencies-centos.html) / [Fedora](developer/install-dependencies-fedora.html) / [Ubuntu](developer/install-dependencies-ubuntu.html)
+    - Installing dependencies on [CentOS](developer/install-dependencies-centos.html) / [Fedora](developer/install-dependencies-fedora.html) / [Gentoo](developer/install-dependencies-gentoo.html) / [Ubuntu](developer/install-dependencies-ubuntu.html)
   - [Building HandBrake for Mac](developer/build-mac.html)
   - [Building HandBrake for Windows](developer/build-windows.html)