bug 1087015 - Improvements to demo studio for smaller header, search pla...

Improvements thus far include:

- [x] Search box no longer displays on small screens; a search icon will instead appear and clicking it will then display the search form
- [ ] Outlines will no longer appear as you click + scroll through demo studio features
- [x] The search placeholder on the main page is now "Search Demos" so as not to be confused with the header search.
- [x] Sped up the demo animations 2x
- [ ] Better display of the demo studio gallery listing pagination - *Don't* show the gallery on the homepage on tiny devices, instead show list of buttons so that the demo home doesn't scroll much.  Also add anchor to pagination images to skip the header (mostly for small devices).
Still useful on desktop, IMO.  Looks bad on mobiles, as mentioned by Vlad