qdoc3: Replace the \i command with \e
qdoc3: Replace the \i command with \e

To get qdoc to render some text in italics,
now you must use \e. \i is no longer accepted.

Task-number:  QTBUG-24578
Change-Id: Ibb8f8d315448c12dc710ea7a36716f7a851126ed
Reviewed-by: Casper van Donderen <808524cef5c654648bea2a2b954f3b3445ed083c@nokia.com>

kobolabs/qtdoc,kobolabs/qtdoc,kobolabs/qtdoc,kobolabs/qtdoc