Collapse large code snippets in README into <details> blocks

[eecavanna]

          I recommend collapsing this snippet into a `<details>` element.

<details>
  <summary>Show/hide snippet</summary>

'''sh
snippet goes here
and
use real backticks instead of single quotes
'''

</details>

Result:

Show/hide snippet

snippet goes here
and
use real backticks instead of single quotes

Originally posted by @eecavanna in #353 (comment)