`@since` annotations should include the package name

[taktoa]

Suppose that a package foo-2.0.1 exposes a module Foo containing an identifier bar that has an @since 2.0.0 attribute in its documentation comment, and then another package baz-1.0.0 reexports Foo.bar from an exposed module Baz. Running Haddock on baz will result in documentation that confusingly says @since 2.0.0 on an identifier exported by a module in a package whose version is only 1.0.0! This could be ameliorated by including in the rendered version of an @since attribute the name of the package the identifier was defined in.

For a concrete example: this says Since 4.9.0.0, even though hedgehog only has version 0.5.3! Perhaps it would also be convenient to make the package name a link, e.g.:

Since: base version 4.9.0.0

Unrelatedly (but relevant since the rendering of @since annotations will have to be changed for this issue), while I like the idea of @since annotations, I think the current way of rendering them clogs up the Haddock output if you put them on everything. When I wrote language-ninja, I actually wrote some ridiculous JS/CSS to make them easier on the eyes: example.

[harpocrates]

See #749. The PR for making Cabal use this option properly should be merged shortly too haskell/cabal#5236.

[gbaz]

@NunoAlexandre maybe this (the obtrusiveness of since) is something that could be addressed in the haddock redesign?

[harpocrates]

@since annotations should include the package name since 978dbc8.