The Generics now contain one Vec of an enum for the generic parameters,
rather than two separate Vec's for lifetime and type parameters.
Additionally, places that previously used Vec<LifetimeDef> now use
Vec<GenericParam> instead.
In `src/libstd/primitive_docs.rs`, a `#[doc(primitive = "unit")]`
section has sat long neglected. This patch teaches rustdoc to recognize
"unit", and steals its trait implementations away from the tuple page.
Rather than (ab)using Debug for outputting the type in plain text use the
alternate format parameter which already does exactly that. This fixes
type parameters for example which would output raw HTML.
Also cleans up adding parens around references to trait objects.
* Don't disambiguate if there are multiple impls for the same type.
* Disambiguate for impls of &Foo and &mut Foo.
* Don't try to disambiguate generic types.
rustdoc: print non-self arguments of bare functions and struct methods on their own line
This change alters the formatting rustdoc uses when it creates function and struct method documentation. For bare functions, each argument is printed on its own line. For struct methods, non-self arguments are printed on their own line. In both cases, no line breaks are introduced if there are no arguments, and for struct methods, no line breaks are introduced if there is only a single self argument. This should aid readability of long function signatures and allow for greater comprehension of these functions.
I've run rustdoc with these changes on my crate egg-mode and its set of dependencies and put the result [on my server](https://shiva.icesoldier.me/doc-custom/egg_mode/). Of note, here are a few shortcut links that highlight the changes:
* [Bare function with a long signature](https://shiva.icesoldier.me/doc-custom/egg_mode/place/fn.reverse_geocode.html)
* [Struct methods, with single self argument and with self and non-self arguments](https://shiva.icesoldier.me/doc-custom/egg_mode/tweet/struct.Timeline.html#method.reset)
* [Bare functions with no arguments](https://shiva.icesoldier.me/doc-custom/rand/fn.thread_rng.html) and [struct methods with no arguments](https://shiva.icesoldier.me/doc-custom/hyper/client/struct.Client.html#method.new) are left unchanged.
This PR consists of two commits: one for bare functions and one for struct methods.
