Allow user to build qtcreator plugins out of qtcreator source tree.

Hi,

It would be great to be able to build Qt Creator plugins out of its source tree.

Why ?

• easier to build plugins
• easier to package

How ?
Like qmmp does :

babali@lotus:~> p -Ql qmmp
qmmp /usr/
qmmp /usr/bin/
qmmp /usr/bin/qmmp
qmmp /usr/include/

1. here qmmp installs it's headers to share the plugin development interface
   qmmp /usr/include/qmmp/
   qmmp /usr/include/qmmp/abstractengine.h
   qmmp /usr/include/qmmp/audioparameters.h
   qmmp /usr/include/qmmp/buffer.h
   qmmp /usr/include/qmmp/decoder.h
   qmmp /usr/include/qmmp/decoderfactory.h
   qmmp /usr/include/qmmp/effect.h
   qmmp /usr/include/qmmp/effectfactory.h
   qmmp /usr/include/qmmp/enginefactory.h
   qmmp /usr/include/qmmp/eqsettings.h
   qmmp /usr/include/qmmp/fileinfo.h
   qmmp /usr/include/qmmp/inputsource.h
   qmmp /usr/include/qmmp/inputsourcefactory.h
   qmmp /usr/include/qmmp/metadatamanager.h
   qmmp /usr/include/qmmp/metadatamodel.h
   qmmp /usr/include/qmmp/output.h
   qmmp /usr/include/qmmp/outputfactory.h
   qmmp /usr/include/qmmp/qmmp.h
   qmmp /usr/include/qmmp/qmmpsettings.h
   qmmp /usr/include/qmmp/recycler.h
   qmmp /usr/include/qmmp/soundcore.h
   qmmp /usr/include/qmmp/statehandler.h
   qmmp /usr/include/qmmp/tagmodel.h
   qmmp /usr/include/qmmp/visual.h
   qmmp /usr/include/qmmp/visualfactory.h
   qmmp /usr/include/qmmp/volumecontrol.h
   qmmp /usr/include/qmmpui/
   qmmp /usr/include/qmmpui/commandlinemanager.h
   qmmp /usr/include/qmmpui/commandlineoption.h
   qmmp /usr/include/qmmpui/detailsdialog.h
   qmmp /usr/include/qmmpui/filedialog.h
   qmmp /usr/include/qmmpui/filedialogfactory.h
   qmmp /usr/include/qmmpui/general.h
   qmmp /usr/include/qmmpui/generalfactory.h
   qmmp /usr/include/qmmpui/generalhandler.h
   qmmp /usr/include/qmmpui/mediaplayer.h
   qmmp /usr/include/qmmpui/metadataformatter.h
   qmmp /usr/include/qmmpui/playlistformat.h
   qmmp /usr/include/qmmpui/playlistitem.h
   qmmp /usr/include/qmmpui/playlistmanager.h
   qmmp /usr/include/qmmpui/playlistmodel.h
   qmmp /usr/include/qmmpui/playlistparser.h
   qmmp /usr/include/qmmpui/templateeditor.h

1. and the the libs for qmmp plugins.
   qmmp /usr/lib/
   qmmp /usr/lib/libqmmp.so
   qmmp /usr/lib/libqmmp.so.0
   qmmp /usr/lib/libqmmp.so.0.5.0
   qmmp /usr/lib/libqmmpui.so
   qmmp /usr/lib/libqmmpui.so.0
   qmmp /usr/lib/libqmmpui.so.0.5.0
   qmmp /usr/lib/qmmp/
   qmmp /usr/lib/qmmp/CommandLineOptions/
   qmmp /usr/lib/qmmp/CommandLineOptions/libincdecvolumeoption.so
   qmmp /usr/lib/qmmp/CommandLineOptions/libseekoption.so
   qmmp /usr/lib/qmmp/CommandLineOptions/libstatusoption.so
   qmmp /usr/lib/qmmp/Effect/
   qmmp /usr/lib/qmmp/Effect/libcrossfade.so
   qmmp /usr/lib/qmmp/Effect/libladspa.so
   qmmp /usr/lib/qmmp/Effect/libsrconverter.so
   qmmp /usr/lib/qmmp/Effect/libstereo.so
   qmmp /usr/lib/qmmp/Engines/
   qmmp /usr/lib/qmmp/Engines/libmplayer.so
   qmmp /usr/lib/qmmp/FileDialogs/
   qmmp /usr/lib/qmmp/FileDialogs/libqmmpfiledialog.so
   qmmp /usr/lib/qmmp/General/
   qmmp /usr/lib/qmmp/General/libcovermanager.so
   qmmp /usr/lib/qmmp/General/libfileops.so
   qmmp /usr/lib/qmmp/General/libhal.so
   qmmp /usr/lib/qmmp/General/libhotkey.so
   qmmp /usr/lib/qmmp/General/libkdenotify.so
   qmmp /usr/lib/qmmp/General/liblyrics.so
   qmmp /usr/lib/qmmp/General/libmpris.so
   qmmp /usr/lib/qmmp/General/libnotifier.so
   qmmp /usr/lib/qmmp/General/libscrobbler.so
   qmmp /usr/lib/qmmp/General/libstatusicon.so
   qmmp /usr/lib/qmmp/General/libudisks.so
   qmmp /usr/lib/qmmp/Input/
   qmmp /usr/lib/qmmp/Input/libcue.so
   qmmp /usr/lib/qmmp/Input/libffmpeg.so
   qmmp /usr/lib/qmmp/Input/libflac.so
   qmmp /usr/lib/qmmp/Input/libmad.so
   qmmp /usr/lib/qmmp/Input/libmodplug.so
   qmmp /usr/lib/qmmp/Input/libmpc.so
   qmmp /usr/lib/qmmp/Input/libsndfile.so
   qmmp /usr/lib/qmmp/Input/libvorbis.so
   qmmp /usr/lib/qmmp/Input/libwavpack.so
   qmmp /usr/lib/qmmp/Output/
   qmmp /usr/lib/qmmp/Output/libalsa.so
   qmmp /usr/lib/qmmp/Output/libjack.so
   qmmp /usr/lib/qmmp/Output/libnull.so
   qmmp /usr/lib/qmmp/Output/liboss.so
   qmmp /usr/lib/qmmp/Output/libpulseaudio.so
   qmmp /usr/lib/qmmp/PlaylistFormats/
   qmmp /usr/lib/qmmp/PlaylistFormats/libm3uplaylistformat.so
   qmmp /usr/lib/qmmp/PlaylistFormats/libplsplaylistformat.so
   qmmp /usr/lib/qmmp/PlaylistFormats/libxspfplaylistformat.so
   qmmp /usr/lib/qmmp/Transports/
   qmmp /usr/lib/qmmp/Transports/libhttp.so
   qmmp /usr/lib/qmmp/Visual/
   qmmp /usr/lib/qmmp/Visual/libanalyzer.so
   qmmp /usr/share/
   qmmp /usr/share/applications/
   qmmp /usr/share/applications/qmmp.desktop
   qmmp /usr/share/applications/qmmp_cue.desktop
   qmmp /usr/share/applications/qmmp_enqueue.desktop
   qmmp /usr/share/icons/
   qmmp /usr/share/icons/hicolor/
   qmmp /usr/share/icons/hicolor/16x16/
   qmmp /usr/share/icons/hicolor/16x16/apps/
   qmmp /usr/share/icons/hicolor/16x16/apps/qmmp.png
   qmmp /usr/share/icons/hicolor/32x32/
   qmmp /usr/share/icons/hicolor/32x32/apps/
   qmmp /usr/share/icons/hicolor/32x32/apps/qmmp.png
   qmmp /usr/share/icons/hicolor/48x48/
   qmmp /usr/share/icons/hicolor/48x48/apps/
   qmmp /usr/share/icons/hicolor/48x48/apps/qmmp.png
   qmmp /usr/share/icons/hicolor/scalable/
   qmmp /usr/share/icons/hicolor/scalable/apps/
   qmmp /usr/share/icons/hicolor/scalable/apps/qmmp-simple.svgz
   qmmp /usr/share/icons/hicolor/scalable/apps/qmmp.svgz
   qmmp /usr/share/qmmp/
   qmmp /usr/share/qmmp/images/
   qmmp /usr/share/qmmp/images/app_icon.png
   qmmp /usr/share/qmmp/images/empty_cover.png
   babali@lotus:~>