Kit: Introduce variables for Kit display names

This change also adds a AbstractMacroExpander for the QtKitInformation.

It supports the following variables in the Kit display name:

 %{Qt:version} - Qt version number
 %{Qt:type}    - Qt type
 %{Qt:name}    - Qt version name
 %{Qt:mkspec}  - mkspec used by the Qt version

Task-number: QTCREATORBUG-11118
Change-Id: I7263781336ab561c34880b187ebd55e81e6ca215
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>

src/plugins/qmakeprojectmanager/qmakeprojectimporter.cpp

@@ -278,7 +278,7 @@ ProjectExplorer::Kit *QmakeProjectImporter::createTemporaryKit(QtSupport::BaseQt
         ki->setup(k);
     }
 
-    k->setDisplayName(version->displayName());
+    k->setUnexpandedDisplayName(version->displayName());
 
     setIsUpdating(true);
     ProjectExplorer::KitManager::registerKit(k);