`instantclick:newpage` event
Add test for links with multiple element

Exposes problem detailed in #65
Clarify underscores as CSS comments
Handle dynamic links (buggy with touch)
Don’t act on mouseover/mousedown if there has been preloading in the last 500ms

Fixes the bug in the last commit, click wouldn’t fire because mouseover/mousedown prevented that, for some reason (haven’t dig).

It introduces a regression though, if you tap near a link, it will not be loaded through InstantClick. Previously, it would load through InstantClick (but be preloaded just 1ms before, on mousedown).

A way to fix that in the future is to preload on click if it hasn’t been done. Currently, no preload on click means InstantClick will redirect to the new page, without pjax. Fixing this may also be useful for those that navigate without their mouses.
Use pjax on click even when there has been no preloading before

Useful because of a regression in 3ca896cda35c8f4ba4c71a1924aab1d4a30709d5 (previous commit), on touch devices when a user taps *near* a link the browser will correct that, but no preloading will have happened.

It’s also useful for non-standard ways to navigate a website, like when using Tab and Return on one’s keyboard to access links.
Reduce number of delays
Allow to alter body and title on receive

Also bring URL on receive, read-only
v3.1.0