New Tmux Vim mappings

    Added support for:
        - normal gnu read line key bindings should work
        - Vim is configured to work with xterm key bindings
        - Vim timeout len is configured to 250
        - Tmux escape timeout len is set to 0 (fixes problem with Vim
          exit escape)
        - Vim and Tmux are using alt keys for pane/window movement
        - Vim Tmux pane management
    TODO's:
        - Vim alt arrow mapping aren't working in Tmux