Add classnames for QML import plugins.

Needed for static builds. qmlimportscanner will
read the "plugin" and "classname" entries.

Change-Id: I31939451366ad3e771d516ac426525c8bcdba57d
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@digia.com>
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Make qmlimportscanner report plugin classnames.

Change-Id: Ifbe72e6dcc569c8cb311d46e4f265da348b353ea
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@digia.com>
Fix the QML import search.

Match the algorithm used by QML, look for the most
specific version of an import first.

Change-Id: Ibf1370af227c8154f657cc2d8a1c1d1ae28d2f39
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@digia.com>