(Maint) Fix warnings issued by yard

There were many uses of incorrect tags (@returns instead of @return),
unnamed params (@params without specifying which param) and inccorect
use of multiple variations (@params for the same param many times
instead of using @overload). This fixes many, but not all of the
warnings issued by yard when it generates documentation.
Merge pull request #1748 from zaphod42/maint/master/fix-many-yard-warnings

(Maint) Fix warnings issued by yard