README function documentation links

[mhpob]

Hyperlinks to functions in the README currently point to the function's code on GitHub. Others are broken.

As {glatos} is now on OTN's R-universe, documentation can be viewed in HTML form. Might this be preferable?

read_glatos_detections, for example:

• Current link (GitHub Code): https://github.com/ocean-tracking-network/glatos/blob/main/R/load-read_glatos_detections.r
• R-universe HTML form: https://ocean-tracking-network.r-universe.dev/glatos/doc/manual.html#read_glatos_detections

This has the added bonus of ignoring file extensions -- the link in the README to read_otn_deployments is current broken as it's looking for ".r" rather than ".R": https://github.com/ocean-tracking-network/glatos/blob/main/R/load-read_otn_deployments.r

Similarly broken

• prepare_tag_sheet
• prepare_deploy_sheet
• REI
• crw_in_polygon