improve search as a primary means to create new pages

Specifically, this pull request checks if the current query is already a
valid pageid and then return that as suggested pageid.

Also, tests are added for this method.

Fixes #2355

PS: We may want to somehow better educate/nudge users to use the better
way of creating pages by creating links on existing pages.

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Typo fix

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print 'you are here' again for startpages

Replace old call to css_styleini

fixes #2330

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This bug was introduced in #2251
c4a386f1

Fixes #2325

Honor type setting for recent changes. fixes #2322

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Fix invalid HTML

Also, for consistency this initializes also $num with 0, while ensuring
that the first FT_SNIPPET_NUMBER results with a $cnt>0 have a snippet.

Punctuation is more natural, makes sense with CSS switched off
and makes screenreaders add a little pause.

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In #2286 the 2nd level heading in the intro was removed, so the h3
should be promoted to h2.

This implements some of the changes discussed in #2314:

1. last mod and number of hits are on the same line and always shown
2. There is a class around the last mod string so it can be
hidden/replaced by an icon
3. All items in the resultBody returned by the event are wrapped in
`<dd>` tags to ensure validity. They get their array key as class
4. There is still a wrapper div around each result for styling purposes

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