Ensures fields returned match API docs and previous versions of
BookStack where we were accidentally returning more fields than
expected.
Updates tests to cover many of these.
Also updated clockwork to ignore image requests for less noisy
debugging.
Also updated chapter page query to not be loading all page data, via new
query in PageQueries.
Added support for mulit-line endpoint descriptions via blank
intermediate lines in php controller method docblocks.
Also tweaks endpoint header design for better flexing and alignment.
