Search box in resource page is too small

[pombredanne]

I find that the search box in the resource page of a project is quickly very small and is therefore hard to use at times.

[tdruez]

One idea would be to integrate a search input in the header, displayed at all time, that would expend into a larger input with extra options to refine the search context.

See also https://github.com/nexB/scancode.io/issues/870