I was just adding tmux plugins to my .tmux.conf file to find out that one of the plugins (tmux-copycat I think) requires tmux 1.9. When I start tmux I get the message `Error: Tmux version unsupported. Please install tmux version 1.9 or greater!". So, what is the best way to upgrade tmux 1.8 to 1.9 on Ubuntu 14.04?
![Ugrade tmux from 1.8 to 1.9 on Ubuntu 14.04](https://cdn-ak-scissors.b.st-hatena.com/image/square/98d6f053a97a87156775f60757c60865d0f2c47d/height=288;version=1;width=512/https%3A%2F%2Fcdn.sstatic.net%2FSites%2Fstackoverflow%2FImg%2Fapple-touch-icon%402.png%3Fv%3D73d79a89bded)