cleanup old branches related to documentation

[fnrizzi]

the followign branches add new content/pages to the docs

i like to move the new content added by these into a single issue so that i can delete the branches but not lose the work which will be resumed later

[antoinemeyer5]

There are 8 branches here:

• 413-multi-vector-update
• 413-max
• 413-min-max
• 413-extent
• 413-dot
• 413-deep-copy
• 413-add-to-diagonal
• 413-abs

And their content are now in the issue https://github.com/Pressio/pressio/issues/631

[fnrizzi]

i did not want to have a new branch, read here please: "move the new content added by these into a single issue" i like to have an issue and put all content there

[antoinemeyer5]

So I copy-paste raw code?

[fnrizzi]

just make an issue, put separate sections and for each section you put the code or you can just upload the file

[antoinemeyer5]

Issue #631 with work carry out by thearusable on issue https://github.com/Pressio/pressio/issues/413