windeployqt: Fix webkit 1.

Split findDependentQtLibraries() such that it returns the
direct dependencies first and their number.

Prevent WebKit1 applications from installing the QML import tree
(triggered by WebKit.dll depending on Quick) checking for direct
dependencies to Quick only.

Print dependencies.

Introduce struct DeployResult, which returns the direct/used/deployed
dependencies, preparing WebKit2-deployment.

Change-Id: I171ca553ee352df2a6f8b0b3d6c0ca72e5c7adab
Reviewed-by: Oliver Wolff <oliver.wolff@digia.com>