rustdoc: Wrong page suggestion on search

Searching `insert` on rustdoc leads [here](http://static.rust-lang.org/doc/master/std/container/MutableMap/trait.MutableMap.html) (broken link) rather than [here](http://static.rust-lang.org/doc/master/std/container/trait.MutableMap.html).

Same for searching `zip`. ([the suggested link](http://static.rust-lang.org/doc/master/std/iter/Iterator/trait.Iterator.html))
