Add instructions for adding the keyboard from the terminal

[somso2e]

A lot of people might not use or have a GUI interface for everything on their system. So a terminal is their only choice.

Instructions:
Add the following command to your ~/.bashrc file:

setxkbmap -layout us,ir -variant ",pes_winkeys" -option grp:alt_shift_toggle

Run . ~/.bashrc.

[cs127]

This isn't specifically for the Windows-style Persian layout. If anyone wanted to add the "Standard" layout that already comes with X11, they would also have to do the same thing if they wanted to use the terminal.

Is this really necessary to be added to this repo?