Windows command line parsing: Do escape backslash.

This will break network paths passed as command line arguments.

Introduced by 4ff6951550cb6e39c3b31895c3af57037e90c9ac .

Task-number: QTBUG-35432
Task-number: QTBUG-30628

Change-Id: Ice9ce15275ef69e9e9e82daf5a303e7c56294368
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Update ChangeLog with new QImage formats

Change-Id: I4023edc29e81a8c29c3259c6024a5a20eda1aeec
Reviewed-by: Jani Heikkinen <jani.heikkinen@digia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>