Add global search to template

[tmotyl]

see https://github.com/TYPO3-Documentation/t3docs-search-indexer https://docs.typo3.org/search/

Make global search input box appear on the right side from the logo.

[tmotyl]

I see that we would also need to adapt the 404 page to mention the new search. @marble can you point me to where is the template of the 404 page located?

[susannemoog]

@tmotyl this one? https://github.com/TYPO3-Documentation/DocsTypo3Org-Homepage/blob/master/Documentation/404.rst ? (click "edit on github" on the 404 :))

[tmotyl]

@tmotyl this one? https://github.com/TYPO3-Documentation/DocsTypo3Org-Homepage/blob/master/Documentation/404.rst ? (click "edit on github" on the 404 :))

oh, right, that was too easy, I was looking for it in wrong repo :)

[marble]

Done! Has been cherry picked as https://github.com/TYPO3-Documentation/sphinx_typo3_theme/commit/a577246b22d656485d1209bba797f1161bef24a3