Add missing background for effect selection list.

Also remove highlight and fix button text color.
Make Menu animation faster.

Task-number: QTBUG-38121
Change-Id: I7d5868d370a8dc7925cee5e694ae043970c569d9
Reviewed-by: Sami Makkonen <sami.makkonen@digia.com>
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>
Selecting something now closes menu

On a closed menu, the text is now hidden.

Task-number: QTBUG-38121
Change-Id: I305fd4f24768115ed21495857cce672d8cbd2135
Reviewed-by: Petref Saraci <petref.saraci@digia.com>
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>
Handle resizing of mainwindow better

Task-number: QTBUG-38121
Change-Id: I877fd5c626418a91850d43de31e71351c14eef25
Reviewed-by: Sami Makkonen <sami.makkonen@digia.com>
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>
Fix documentation of qmlvideofx example

Make the documentation fit to the current state of the example.

Task-number: QTBUG-38121
Change-Id: I3379e3328d07ef8bcdb35a5e3821ab194c3443c4
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@digia.com>
Reviewed-by: Sami Makkonen <sami.makkonen@digia.com>
Reviewed-by: Yoann Lopes <yoann.lopes@digia.com>