Edit rack install and configuration file

[kmsholcomb]

In addition to my copy edits, I'd like the reviewer to consider the following questions/suggestions:

• At the end of the "Install the CLI" section, considering adding a section for upgrading the binary.
• Under "Interactive configure command," I added a paragraph explaining the placeholders used in the configuration file. I am not sure if my explanation of the region value is accurate. Revise as necessary.

[jrperritt]

At the end of the "Install the CLI" section, considering adding a section for upgrading the binary.

will do; there's some work to be done around that. related to #397

I am not sure if my explanation of the region value is accurate.

looks good to me

+2