Add changes-5.1.1 file

Change-Id: I6812e032b566ecd53459dfde394058e198119e9f
Reviewed-by: Jerome Pasion <jerome.pasion@digia.com>
Doc: Document changes to Qt::HANDLE in C++ API Changes page

Qt::HANDLE is always defined as 'void *' on Qt 5.0

Task-number: QTBUG-32469
Change-Id: I945e436dec45a31a99d04b1221e9dad1fbd10476
Reviewed-by: Jerome Pasion <jerome.pasion@digia.com>
Doc: Replace 'Learn More' subsections with bolded text

Getting Started Programming with Qt Widgets has multiple subsections
titled 'Learn More'. They appear in TOC but do link to correct
sections.

This change fixes the issue by replacing these sections with bolded
text so they are not listed in TOC.

Task-number: QTBUG-32110
Change-Id: I4fbabcc18dc15737f5a155c742a82cefe57ba17d
Reviewed-by: Jerome Pasion <jerome.pasion@digia.com>
Document the deprecation of setRoleNames

The API was deprecated in qtbase to make the QAbstractItemModel API more
consistent. Hence, it is now being put in the porting guide to simplify the
effort for the Qt users.

Task-number: QTBUG-31684
Change-Id: I9350f7752accd90b8fcc9f2a6d53554e3a1e3dd2
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>
Merge remote-tracking branch 'origin/release' into stable

Change-Id: I316359874afb67c824980d627527adbe57b2f10d