lupdate: Automatically pick up translatable strings in .qml/.js files that are part of the deployment directory

The Qml Application wizard that we ship with QtCreator 2.1 advocates putting all .qml/.js files in a directory that will be deployed alongside with the executable. However, running lupdate on the .pro file doesn't pick up translatable strings from these files.

Running lupdate on the .pro file should also inspect the deployment folders.

Workaround for the time being:

lupdate HelloWorld.pro -ts app.ts // get strings from C++ sources
lupdate qml -ts qml.ts // get strings from qml folder
lconvert app.ts qml.ts -o project.ts