Reduce @see tags

[joemcgill]

As I understand it, @see attributes should really only reference one function name. In the cases where both wp_get_attachment_sizes() and wp_calculate_image_sizes() are referenced, I would opt for the function being used, which is generally wp_get_attachment_sizes().

• PHPDocs manual: http://manual.phpdoc.org/HTMLSmartyConverter/HandS/phpDocumentor/tutorial_tags.see.pkg.html
• WP Docs: https://make.wordpress.org/core/handbook/best-practices/inline-documentation-standards/php/#docblock-formatting

[jaspermdegroot]

In the phpDoc manual I read "...unlimited number of values separated by commas". Nevertheless, I agree that just referring to wp_get_attachment_image_sizes() is sufficient. There we refer to `wp_calculate_image_sizes(). The same goes for the srcset functions. I also noticed that we should wrap the function names in quotes or backticks. Will update this PR.

Update: Actually we don't use @see in wp_get_attachment_image_sizes() to refer to wp_calculate_image_sizes() but I think it's fine to just refer to wp_get_attachment_image_sizes()

[jaspermdegroot]

Manually merged