adding an example on how to customize the iso image with other packages

[nickgaw]

I was trying to build the iso image adding all required packages to build it into the image so when I do the customized installation this iso is ready for building new versions of itself automatically. I was not able to find any examples for how to do this and think that some documentation should exist for this process as well as a way to remove languages that you don't speak so to add packages that you yourself would need to make the custom installation more useful. I am also totally blind and would like it if during the installation if you turn on orca with alt and windows and s during the installation or recovery partition that the setting is carried over to the installed system regardless of what method is used to install it either iso or recovery partition.<!--

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