Minor docs improvements

[jackkoenig]

This was primarily motivated by noticing https://www.chisel-lang.org/chisel3/docs/explanations/blackboxes.html#blackboxes-with-verilog-in-a-resource-file currently has messed up formatting. I fixed some other things in the process and updated the docs for Bundle literals which are woefully out-of-date.

• Fix some botched formatting (replace ```mdoc scala with ```scala mdoc)
• Replace some unnecessary uses of triple backticks with single
  backticks
• Move appendix docs from wiki-deprecated/ to appendix/
  • This will require an update on the website as well
• Update Bundle literal docs

Contributor Checklist

• [NA] Did you add Scaladoc to every public function/method?
• Did you add at least one test demonstrating the PR?
• Did you delete any extraneous printlns/debugging code?
• Did you specify the type of improvement?
• Did you add appropriate documentation in docs/src?
• Did you state the API impact?
• Did you specify the code generation impact?
• Did you request a desired merge strategy?
• [NA] Did you add text to be included in the Release Notes for this change?

Type of Improvement

• documentation

API Impact

No impact

Backend Code Generation Impact

No impact

Desired Merge Strategy

• Squash

Release Notes

Reviewer Checklist (only modified by reviewer)

• Did you add the appropriate labels?
• Did you mark the proper milestone (3.2.x, 3.3.x, 3.4.0, 3.5.0) ?
• Did you review?
• Did you check whether all relevant Contributor checkboxes have been checked?
• Did you mark as Please Merge?

[mwachs5]

great!

[chick]

lgtm