Document the using with with-open

Hello!

First of all, thanks for failjure

I would be glad if you write an example how to use failjure for cases, where a user needs to close opened resources in any case. E.g. I’m doing the next:

(f/attempt-all [reader (pdf-reader source)
document (pdf-document reader)
fields (fields document)]
(do
(.close document)
(.close reader)
fields)
(f/when-fail [e]
; Here I do not have an access to reader and document
; to close them
))

I wonder if there any mechanism to close the `document` and the `reader` in any case, like with `with-open`

Start by reviewing the existing failjure documentation and the usage of `attempt-all` and `when-fail`. Add an example showing how resource cleanup can be handled with `with-open`, including the failure case, and make the documented behavior clear for readers working with opened resources.

Written by the indexing model from the issue text.