Minimal plugin: Use a dummy font database for command line tools.

Suppress warnings like:
QFontDatabase: Cannot find font directory '...' - is Qt installed correctly?
occurring for example when using qmlplugindump.

Add option flags (similar to Windows plugin) to the integration
class to be used for QT_DEBUG_BACKINGSTORE and other functionality.

Add a dummy font database with empty populate() function to be
used unless the debug flag for the backing store is used.

Task-number: QTBUG-33674
Task-number: QTCREATORBUG-10685
Change-Id: I7eaff3025de12e6b0471a3430f986b0cd810e22c
Reviewed-by: Paul Olav Tvete <paul.tvete@digia.com>
QBBSystemLocale: Do not set fixed buffer size when reading pps objects

Set dynamically the buffer size when reading pps objects since a pps file
size is not always fix.

Change-Id: I48f80389161bfbce3342e53ceec0b13bb7df0e4c
Reviewed-by: Tony Van Eerd <tvaneerd@blackberry.com>
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>
Doc: Corrected link to Graphicsview Examples

Task-number: QTBUG-34749
Change-Id: I66251e4b40e2930b08ed4bd932aef60aae7ebaa4
Reviewed-by: Topi Reiniö <topi.reinio@digia.com>