[LINUX MINT] Install latest tmux

$ [sudo] apt-get update \
>   && [sudo] apt-get install \
>       -y python-software-properties software-properties-common \
>   && [sudo] add-apt-repository -y ppa:pi-rho/dev \
>   && [sudo] apt-get update \
>   && [sudo] apt-get install -y tmux-next