docs: fix scrollbar ascii illustrations and calendar doc paths

[SLASHLogin]

This PR fixes scrollbar's documentation, which tried to showcase its elements. This requires for the text to be rendered exactly how it was written, which isn't the case for the cargo and other tools. Thus, it requires to be wrapped inside text blocks, which preserves text as is.
Secondly, there were problems with doc paths in calendar's documentation.
Finally, recently merged changes in block.rs were not formatted properly

[codecov]

Codecov Report

Merging #272 (ca454a3) into main (a04b190) will not change coverage.
The diff coverage is n/a.

❗ Current head ca454a3 differs from pull request most recent head 27e59aa. Consider uploading reports for the commit 27e59aa to get more accurate results

@@           Coverage Diff           @@
##             main     #272   +/-   ##
=======================================
  Coverage   82.50%   82.50%           
=======================================
  Files          36       36           
  Lines        7301     7301           
=======================================
  Hits         6024     6024           
  Misses       1277     1277           

Impacted Files	Coverage Δ
src/widgets/block.rs	83.29% <ø> (ø)
src/widgets/calendar.rs	82.30% <ø> (ø)
src/widgets/scrollbar.rs	87.71% <ø> (ø)

[mindoodoo]

Nice catch ! Thanks for the PR.

[kdheepak]

Thanks for catching that! Is it possible to have a doc preview on each PR?

[SLASHLogin]

Thanks for catching that! Is it possible to have a doc preview on each PR?

I'm not aware of any way to do that. Personally, I just use cargo-watch when creating PR and/or editing documentation. But when reviewing, you'd have to download the PR and run it locally.

[mindoodoo]

Didn't know about cargo-watch, looks awesome ! Definitely adding it to my workflow.

[SLASHLogin]

Sorry, I had to sign the commits for this to be merged. It would be nice to include that information in the CONTRIBUTING.md