New targets added

Red Hat 6.5 and Windows 8.1 nodes, and MinGW 4.8.2 target added.

Change-Id: I0c1dc38591c8accd9a79700a8c5e4428e0d904bf
Reviewed-by: Heikki Halmet <heikki.halmet@digia.com>
Testconfig: Adding QtWebsockets stable and release jobs into ci.

Following same enforcings as dev, while first ci build from stable,
and eventually release, should have CI tested baselines.

Change-Id: Ic0dc2e1054d19dceadfc7832602c71f6bcb4d567
Reviewed-by: Tony Sarajärvi <tony.sarajarvi@digia.com>
Reviewed-by: Sergio Ahumada <sahumada@blackberry.com>