change r5r instalation instructions

[temospena]

• [x] change r5r installation instructions (software.qmd)
• [x] add link to external materials of accessibility with r5r (r5r.qmd)
• [x] change the name in module title and course structure (remove "routing")

@rafapereirabr if you want you can directly change this or I also can do that. Thanks!

[rafapereirabr]

thanks, @temospena !