[TMUX] Update copy/paste keybindings to tmux 2.4
[TMUX] Update copy/paste keybindings to tmux 2.4

This change is necessary due to incompatible changes in version 2.4
that have change key tables.

More information: https://github.com/tmux/tmux/blob/2.4/CHANGES

JesusMtnez/dotfiles,JesusMtnez/dotfiles