Fix the condition for the WiX and NSIS imports.

Change-Id: I458175a3462907a1b9b0d3bb83533207557c6517
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
prioritize artifacts by product when building

To prevent disk cache misses, esp. when using precompiled headers, we're
prioritizing the artifacts we're building by product.

Task-number: QBS-460

Change-Id: Iff2373147c2fe6f86ac79c9785c8c89260aba5b4
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>