README.md: adjust markdown formatting

[vazhnov]

• Remove extra spaces.
• Fix extra capitalization.
• Use list formatting.
• No logic changes were made, only formatting improvements.

I'm not sure how to format properly these phrases:

WE NEED A HARDWARE DONATION TO MAKE ARM64 IMAGES THIS SHOULD, WE HOPE, IN THE WORKS

Actually I wanted to add information about a license (add a new chapter in README.md), according to #19, #253, #264. But I found the whole README.md requires some refreshing first :)

[vazhnov]

The resulting rendered README can be viewed here: https://github.com/vazhnov/robox/blob/Readme_adjust_markdown_formatting/README.md

[vazhnov]

but only on build robots equipped with SSDs or NVMe drives,

Should "roboxes" be here ^^^ ?

[vazhnov]

Ping!

[vazhnov]

:)